How Reddit Citations Changed in ChatGPT for High-Stakes Investing, Retirement, Mortgage and Financial Consumer Decisions

LLM Authority Index Research | ChatGPT | Investing, Retirement, Mortgage and Financial Decisions | July-September 2026

Reddit's visible citation role in ChatGPT fell sharply across high-stakes investing, retirement, mortgage and financial consumer questions between July and September 2026.

The locked ChatGPT endpoint published in the parent financial Reddit study shows Reddit citation-event share falling from 8.87% in July to 2.26% in September, a 74.6% relative decline. Response citation coverage fell from 28.41% to 7.98%, down 71.9%.

The matched result is even more striking. In the locked parent-study ChatGPT subset, 169 prompt-plus-surface scenarios were paired between July and September. Reddit disappeared in 38 and newly appeared in only 4, a 9.5-to-1 loss-to-gain ratio. Matched response coverage fell from 26.63% to 6.51%.

A fresh platform-specific audit of the frozen record-level corpus points in the same direction. All 11 financial verticals declined in both Reddit citation-event share and response coverage from July to September. The median event-share decline across the 11 verticals was 74.1%.

Answer Capsule

Reddit citation visibility declined sharply in ChatGPT for high-stakes investing, retirement, mortgage and financial decisions from July to September 2026. On the locked platform endpoint, Reddit citation-event share fell 74.6%, from 8.87% to 2.26%, while response citation coverage fell 71.9%, from 28.41% to 7.98%. In the locked matched panel, 169 scenarios were paired: Reddit remained cited in 7, disappeared in 38, newly appeared in 4, and was absent in 120. The exact two-sided McNemar p-value is approximately 5.65e-08.

Key Findings

• Locked Reddit citation-event share fell from 8.87% to 2.26%, down 74.6%.
• Locked Reddit response citation coverage fell from 28.41% to 7.98%, down 71.9%.
• The locked strict matched set contained 169 scenarios: 7 both, 38 losses, 4 gains, and 120 neither.
• Matched response coverage fell from 26.63% to 6.51%, down about 75.6%.
• Reddit was 9.5 times more likely to disappear than to newly appear among discordant matched scenarios.
• The exact two-sided McNemar test gives p approximately 5.65e-08.
• In the fresh three-month ChatGPT financial panel, Reddit response coverage moved from 28.44% in July to 15.38% in August and 8.05% in September.
• Reddit's fresh monthly response-level rank moved from #2 to #6 to #9.
• In the fresh platform-specific vertical audit, all 11 financial verticals declined in both Reddit event share and response coverage.
• The median vertical decline was 74.1% in event share and 69.3% in response coverage.
• The steepest event-share declines were Structured Settlements (-100.0%), Online Financial Advisors (-95.5%), Online Stock Brokers (-85.5%), Crypto Exchanges (-84.7%), and Robo-Advisors (-78.1%).
• In the fresh 39-scenario Reddit-loss audit, no single source replaced Reddit. CoinBureau.com newly appeared in 25.6% and Finder.com in 15.4% of loss scenarios.

Questions This Study Answers

• How much did Reddit citation visibility change in ChatGPT for high-stakes financial decisions from July to September 2026?
• Does the decline remain when the same prompt and ChatGPT surface are paired?
• Which financial verticals and replacement sources changed most as Reddit visibility fell?

Why This Research Belongs in Daily AI Search Marketing Decisions

Article 51 isolates one source, Reddit, inside one platform, ChatGPT, and one commercial decision family, Investing, Retirement, Mortgage and Financial Decisions. That narrow design makes the study useful for day-to-day AI search marketing because it separates four different questions that are often collapsed into one visibility score:

1. Where does Reddit rank inside the ChatGPT financial source market?
2. How often is Reddit actually cited, measured both as citation-event share and response citation coverage?
3. Does the same prompt-plus-surface scenario keep or lose Reddit over time?
4. Is Reddit-specific decline occurring inside a stable source market or inside a source market that is itself rotating quickly?

In the three-month ChatGPT financial source study, Reddit still ranked #3 overall at 17.8% response citation coverage. That aggregate position can coexist with a severe current-month decline: Reddit ranked #2 in July, #6 in August and #9 in September, while the fresh monthly response coverage fell from 28.44% to 15.38% to 8.05% and fresh citation-event share fell from 8.77% to 5.32% to 2.36%.

The locked endpoint is even more useful for cross-article comparison. Reddit citation-event share fell 74.6%, from 8.87% to 2.26%, while response citation coverage fell 71.9%, from 28.41% to 7.98%. In the locked matched set, 38 scenarios lost Reddit while only 4 gained it, a 9.5-to-1 loss-to-gain ratio, and matched coverage fell from 26.63% to 6.51%, about a 75.6% decline.

For publishers, that means a strong three-month aggregate position should not be presented as proof that current visibility is stable. For financial brands and CMOs, it means ChatGPT source strategy should be monitored with a fixed prompt panel and separate measures for rank, response coverage, citation-event share, and matched losses and gains.

Article 51 also needs to be interpreted inside a comparatively unstable ChatGPT financial source market. The ChatGPT financial source study reports that the Top 100 account for 69.7% of domain-response appearances, yet only 50 domains remained in the Top 100 in July, August and September and the median monthly Top 100 Jaccard similarity was only 38.9%. The source market is concentrated at the top but rotates substantially over time.

That broader churn does not explain away the Reddit result. The same-prompt matched panel produced 38 Reddit losses versus 4 gains, and all 11 financial verticals declined in both Reddit event share and response coverage in the fresh child audit. The median vertical decline was 74.1% in event share and 69.3% in response coverage. The Reddit-specific signal is therefore much stronger than simply observing that ChatGPT's source list changed.

The platform comparison is equally important. The locked parent financial study reports Reddit citation-event share changes of -74.6% in ChatGPT, -23.5% in Google AI Overviews, -22.9% in Google AI Mode, -15.3% in Gemini, -87.0% in Perplexity, and no measurable Reddit event share in Microsoft Copilot at either endpoint. One blended 'Reddit visibility in AI' score would hide those differences.

The broader Investing, Retirement, Mortgage and Financial Citation Authority Study reports 66.7% median monthly Top 100 persistence, 28.2% median cross-platform Top 100 portability, and an approximate 38.5 percentage-point Persistence-Portability Gap. It also reports 19 domains appearing in all six platform Top 100 lists.

ChatGPT's own financial source market answers a narrower question. Its 38.9% median monthly Top 100 persistence is much lower than the financial-family persistence figure, and its final child-study Top 100 overlaps are 54 domains with Google AI Overviews, 52 with Google AI Mode, 41 with Perplexity, 41 with Gemini and 40 with Microsoft Copilot. Those pairwise overlaps are useful context, but Article 51 should not manufacture a new Persistence-Portability Gap from one platform-specific temporal metric and one pairwise overlap.

The Persistence-Portability Gap framework therefore helps interpret Article 51 correctly: decision-family authority can be more persistent over time than portable across engines, while an individual platform source market can still rotate quickly and an individual source inside it can decline even faster.

There is also a financial-family portability versioning note. Article 07 reports 28.2% median cross-platform portability, while recomputing the final child-study Top 100 lists produces about 27.4%. The published 28.2% remains the authoritative parent value until the entire financial family is rerun through one consolidated pipeline. Article 51 should not silently mix those versions.

There are two additional source-analysis version distinctions that should remain visible. First, the frozen Article 07 parent category table reports 1,348 ChatGPT responses, while the later Article 23 source study reports 1,373. Second, Article 23 publishes 6,700 visible citation events and 5,871 domain-response appearances after its stricter public-infrastructure filter, while the later child reconstruction resolves 6,721 events and 5,879 appearances before that filter. Article 51 keeps those versions separate rather than silently merging them.

Citation visibility should remain separate from brand mentions, recommendation rate, rank, sentiment, citation-recommendation coupling, and downstream business outcomes. This study measures the visible source layer. It does not establish that a Reddit citation caused a lender, adviser, exchange, publisher, mortgage company, investment platform, or product recommendation.

Commercial Action Matrix: What Publishers and CMOs Can Do With the Findings

Where Article 51 Fits in the High-Stakes Consumer Decisions Corpus

Article 51 is a child analysis of two parent studies:

• the Financial Reddit decline study, which provides the locked cross-platform financial endpoint and matched counts; and
• the ChatGPT Financial source study, which provides the surrounding three-month ChatGPT source market, including Reddit's #3 aggregate rank and 17.8% response coverage, 50 domains present in all three monthly Top 100s, and 38.9% median monthly Top 100 persistence.

The platform-level context comes from the overall ChatGPT Top 100 study. The broader interpretation comes from the 2026 AI Citation Authority Study, the overall Reddit decline study, the cross-platform citation-overlap study, the citation-drift study, and the Persistence-Portability Gap framework. Those studies answer different questions and should not be collapsed into one visibility score.

What We Studied

This article is the ChatGPT platform-specific extension of the broader Reddit decline study for high-stakes investing, retirement, mortgage and financial consumer decisions.

The underlying published ChatGPT financial source study contains:

The 11 source vertical labels are:

1. Annuities
2. Crypto Exchanges
3. Crypto Wallets
4. Gold IRAs and Precious Metals Dealers
5. Mortgage
6. Mortgage Refinance Lenders
7. Online Financial Advisors
8. Online Stock Brokers
9. Reverse Mortgage
10. Robo-Advisors
11. Structured Settlements

All 11 verticals were represented in both July and September. No vertical had to be removed from the endpoint because of a missing July source dataset.

A later direct child-study reconstruction of the frozen record-level corpus returns the same 1,373 eligible responses but 6,721 domain-resolved citation events and 5,879 domain-response appearances before the stricter public-infrastructure filtering reflected in Article 23. This article keeps the published source-study totals for source-market description and the locked Article 29 values for cross-series endpoint comparisons.

The Core Finding: Reddit Collapsed on the Locked ChatGPT Financial Endpoint

Questions This Section Answers

• Did Reddit lose both event share and response coverage?
• How large was the ChatGPT-specific decline?
• Was the decline steeper than on Google's AI surfaces?

Yes. Both Reddit metrics fell sharply on the locked ChatGPT financial endpoint.

The parent financial Reddit study reported a 33.1% all-platform decline in Reddit citation-event share. ChatGPT declined more than twice as much on a relative basis.

The two Google financial surfaces moved very differently. Google AI Overviews declined 23.5% in event share and Google AI Mode declined 22.9%. Perplexity declined even more sharply than ChatGPT at 87.0%.

Commercially, this is not a minor rank fluctuation. Reddit moved from being a major ChatGPT source for financial prompts to a much smaller visible source within the same quarter.

Reddit Fell Across the Full Three-Month ChatGPT Financial Panel

Questions This Section Answers

• Was the September decline part of a three-month pattern?
• Did Reddit lose rank as its coverage fell?
• How does the fresh monthly reconstruction compare with the locked endpoint?

The fresh record-level monthly panel also shows a steep, sequential decline:

The response-level pattern is close to the locked parent endpoint: 28.44% in July, 15.38% in August, and 8.05% in September. The locked endpoint reports 28.41% to 7.98% because the parent trend study uses the published cross-series screening contract.

The fresh citation-event share falls from 8.77% to 5.32% to 2.36%. The locked Article 29 endpoint is 8.87% to 2.26%. The slight difference reflects the child reconstruction's record-level citation handling, not a directional disagreement.

Reddit's fresh response-level rank moved from #2 in July to #6 in August and #9 in September.

The Strict Matched-Prompt Test Shows Almost Ten Losses for Every Gain

Questions This Section Answers

• Did Reddit decline when prompt wording and ChatGPT surface were held constant?
• How many matched scenarios lost Reddit compared with gains?
• Was the directional imbalance statistically meaningful inside this sample?

The locked Article 29 ChatGPT matched panel contains 169 scenarios:

Reddit losses outnumbered gains 38 to 4, a 9.5-to-1 imbalance.

Matched Reddit response coverage fell from 26.63% to 6.51%, approximately a 75.6% relative decline.

The exact two-sided McNemar test gives p approximately 5.65e-08. Within this matched sample, the loss-gain imbalance is highly inconsistent with a simple 50/50 turnover process. The test does not identify why Reddit disappeared from a response.

A later direct record-level reconstruction produces 173 unambiguous pairs, with 7 both, 39 losses, 4 gains and 123 neither. It yields the same directional conclusion. This article preserves the published 169-scenario parent panel for series consistency and uses the fresh reconstruction for the replacement-source audit below.

Every Financial Vertical Declined in the Fresh ChatGPT Audit

Questions This Section Answers

• Was the decline broad across the 11 financial verticals?
• Which topics lost the most Reddit visibility?
• Which topics were relatively more resilient?

The fresh platform-specific audit shows unusually broad decline. All 11 verticals fell in both Reddit event share and response coverage.

The median vertical event-share decline was 74.1%. The median response-coverage decline was 69.3%.

The steepest event-share declines were:

1. Structured Settlements: 13.58% to 0.00%, down 100.0%.
2. Online Financial Advisors: 11.39% to 0.51%, down 95.5%.
3. Online Stock Brokers: 7.39% to 1.07%, down 85.5%.
4. Crypto Exchanges: 8.48% to 1.29%, down 84.7%.
5. Robo-Advisors: 10.26% to 2.25%, down 78.1%.

Even the most resilient measured vertical, Mortgage Refinance Lenders, declined 31.6% in event share and 27.7% in response coverage.

The fresh audit therefore does not depend on one or two unusually weak verticals. It shows a platform-wide reduction in Reddit citation visibility across the entire financial family.

What Appeared When Reddit Disappeared?

Questions This Section Answers

• Did one source consistently replace Reddit?
• Which domains appeared most often in fresh Reddit-loss scenarios?
• Does the evidence support a one-for-one replacement strategy?

No single source replaced Reddit across the fresh 39 matched scenarios where Reddit appeared in July but not September.

CoinBureau.com was the most common newly appearing source, but it appeared in only 25.6% of the fresh Reddit-loss scenarios. Finder.com appeared in 15.4%. Several financial and investing publishers, including Forbes, Fidelity, NerdWallet, Kiplinger, Schwab and StockBrokers.com, each appeared in 7.7%.

The pattern supports source redistribution, not a one-for-one replacement. The newly appearing sources span financial publishers, broker and investing specialists, crypto publishers, exchanges and first-party investment platforms.

For brands, that matters. A strategy that simply replaces Reddit outreach with one publisher target would miss most of the source movement visible in this panel.

Platform Differences: ChatGPT Declined Far More Than Google's AI Surfaces

Questions This Section Answers

• Was the Reddit decline similar across AI platforms?
• How did ChatGPT compare with Google AI Overviews, Google AI Mode and Perplexity?
• Why should financial teams report source visibility by platform?

The parent financial study shows large platform differences:

ChatGPT's decline was more than three times the relative event-share decline measured on either Google surface. Only Perplexity declined more sharply in this financial family.

The matched tests show the same divergence. ChatGPT had 38 losses vs. 4 gains, compared with 60 vs. 22 in Google AI Overviews, 79 vs. 25 in Google AI Mode, and 16 vs. 0 in Perplexity.

A single blended Reddit visibility KPI would therefore obscure the operational reality. Financial brands and publishers should report citation visibility by platform, not as one pooled score.

What This Means for Financial Brands and CMOs

Questions This Section Answers

• Should financial brands abandon Reddit because ChatGPT citations fell?
• What should replace a single-source authority strategy?
• Which measurements matter most after a source-market shift?

1. Do not equate a citation decline with the end of Reddit's value

This study measures visible ChatGPT citations, not Reddit's effect on brand discovery, model training, social proof, user research or recommendation language. A decline in one visible source channel does not answer those separate questions.

2. Treat ChatGPT as its own source market

Google AI Overviews and Google AI Mode retained substantially more Reddit visibility. A campaign can therefore appear stable in blended reporting while losing a large share of its ChatGPT source exposure.

3. Diversify third-party authority

The fresh loss scenarios redistributed across Coin Bureau, Finder, Forbes, Fidelity, NerdWallet, Kiplinger, Schwab, StockBrokers.com, exchanges and first-party platforms. Build a portfolio of credible sources rather than a single replacement target.

4. Separate citations from mentions and recommendations

Track visible citations, brand mentions, recommendation rate, comparison placement, sentiment, first-party citations and third-party citations as different metrics. Citation visibility does not prove recommendation causality.

5. Manage at the prompt-cluster level

Online Financial Advisors, Online Stock Brokers, Crypto Exchanges and Structured Settlements lost Reddit visibility at different rates. Budget and editorial strategy should follow the commercial prompts that matter to the business rather than one family average.

What This Means for Financial Publishers

Reddit's ChatGPT decline creates opportunity, but not automatic transfer.

A publisher can use the same fixed prompt set to show where its own domain gains or loses ChatGPT visibility as the source market changes. The strongest commercial proof is not a generic claim that ChatGPT cites the publisher. It is measured response coverage for defined high-intent prompt clusters with repeatable denominators.

Publishers should monitor:

• response citation coverage by vertical and prompt cluster;
• citation-event depth and unique cited URLs;
• persistence across repeated monthly pulls;
• appearance in matched scenarios where Reddit disappears;
• cross-platform visibility in ChatGPT, Google AI Overviews and Google AI Mode; and
• whether citation gains coincide with brand mentions or recommendations.

The defensible claim is measured citation visibility, not "ChatGPT trusts us" or "our citation caused the recommendation."

How This Study Relates to Prior Reddit and Financial AI Research

Independent research is directionally consistent with a sharp Reddit decline in ChatGPT during the same quarter, but the exact percentages are not directly comparable.

PromptWatch measured Reddit's share of ChatGPT Search citations averaging 3.83% from July 18 through August 7, 2026, then falling to 0.52% from August 14 through August 17, an 86.4% relative decline. It also measured ChatGPT's use of domain-scoped site: fan-out queries jumping from 0.37% to 16.8% on August 8. Article 51 shows a similarly sharp directional break in a different population: fresh ChatGPT financial response coverage moved 28.44% to 15.38% to 8.05% from July through September, while the locked endpoint declined 71.9%.

Search Engine Journal reviewed the PromptWatch timing and cautioned that the August 8 search-behavior change does not fully explain the sharper August 14 Reddit collapse. PromptWatch itself described the size of the drop as provisional and could not rule out a collection issue. Article 51 therefore treats the timing as contextual evidence, not proof that a specific retrieval, ranking, licensing or product change caused the financial decline.

Ahrefs' September 2026 broad U.S. ChatGPT leaderboard still ranked Reddit #1 at 16.8% mention share, followed by Wikipedia at 7.0%, Consumer Reports at 3.7% and Forbes at 3.1%. That broad all-topic prominence can coexist with Reddit ranking #3 at 17.8% response coverage across this three-month financial source study and only #9 at 8.05% coverage in September. Ahrefs uses a broad U.S. query universe and a mention-share denominator, while Article 51 uses high-stakes financial prompts and reports response citation coverage plus citation-event share.

BrightEdge's August 2026 finance analysis found a relatively flat ChatGPT source curve: the five leading sources appeared in roughly 19%, 15%, 14%, 14% and 11% of tracked finance prompts, compared with 51%, 29%, 19%, 19% and 18% on Google AI Overviews. BrightEdge measured one week in a different finance prompt set, so the percentages should not be merged with Article 51. The useful agreement is structural: ChatGPT's finance source market can be materially different from Google's even inside the same broad category.

Tinuiti's Q3 2026 citation research reports that most tracked AI platforms were at or near Q3 highs in overall social citation share, with Perplexity as a notable exception. That broader social-source movement can coexist with a Reddit-specific ChatGPT decline because the social category and one social domain are different measurements.

Taken together, the outside research strengthens the case for measurement discipline, not a universal Reddit narrative. The defensible comparison is direction, platform specificity, population and methodology, not decimal-point equivalence across unrelated panels.

How This Study Is Different

This study narrows the broader Reddit trend research to one platform, one high-stakes commercial family and one fixed three-month window.

It combines:

1. a 1,373-response published ChatGPT financial source slice;
2. a locked July-to-September ChatGPT endpoint;
3. a 169-scenario locked matched prompt-plus-surface test;
4. both citation-event share and response citation coverage;
5. a fresh 11-vertical platform-specific audit from the frozen source corpus; and
6. a fresh matched Reddit-loss source redistribution audit.

The question is narrow and commercial: how stable was Reddit as a directly cited source in ChatGPT for consequential financial consumer decisions during this quarter?

Why AI Citation Studies Can Disagree

Two well-executed studies can report different Reddit trends without either one necessarily being wrong.

Query population

Mortgage, investing, retirement and crypto questions are not representative of the entire web. Reddit's role can differ in software, travel, entertainment, troubleshooting and general informational queries.

Platform surface

ChatGPT can behave differently from Google AI Overviews, Google AI Mode, Gemini, Perplexity and Microsoft Copilot.

Denominator

Citation-event share and response citation coverage measure different things. A source can lose event share faster or slower than response coverage.

Time window

A short product change and a three-month endpoint comparison answer different questions.

Prompt weighting

This study does not weight prompts by search volume, media spend, assets under management, loan value, conversion probability or revenue.

Matching contract

The locked parent matched panel contains 169 ChatGPT scenarios. The later record-level child reconstruction yields 173 unambiguous pairs, with one additional loss, while preserving the same broader direction. This article uses the published parent denominator for cross-series consistency and discloses the reconstruction difference rather than silently merging the two.

Public infrastructure filtering

Article 23 published 6,700 visible citation events and 5,871 domain-response appearances after its public infrastructure filter. The later child reconstruction resolves 6,721 citation events and 5,879 domain-response appearances before that stricter filter. This small difference affects descriptive event denominators, not the locked headline endpoint.

The useful conclusion is not that one universal Reddit citation percentage exists. Citation visibility is conditional on platform, category, prompt set, time period, denominator and collection method.

Verticals Covered

The ChatGPT financial study covers all 11 family verticals:

• Annuities
• Crypto Exchanges
• Crypto Wallets
• Gold IRAs and Precious Metals Dealers
• Mortgage
• Mortgage Refinance Lenders
• Online Financial Advisors
• Online Stock Brokers
• Reverse Mortgage
• Robo-Advisors
• Structured Settlements

All 11 were present at both July and September endpoints.

Methodology

Source archive

This study uses the frozen July-September 2026 LLM Authority Index archive underlying the financial citation-source study and the parent financial Reddit decline study.

Eligibility

A record is eligible when it is:

• in July, August or September 2026;
• assigned to the ChatGPT platform family;
• associated with the Investing, Retirement, Mortgage and Financial Decisions family; and
• not explicitly marked as an extraction failure.

Exact-repeat anti-double-counting

An observation is treated as an exact analytical repeat when all of the following match:

• report month;
• exact raw platform/source surface;
• normalized prompt text; and
• exact set of original citation URLs.

One analytical record is retained while source-dataset memberships are preserved for vertical analysis.

Prompt normalization

Prompt text is normalized with Unicode NFKC normalization, case folding, whitespace collapse and trimming.

Domain normalization

Citation URLs are parsed to hostname, lowercased, stripped of a leading www., and consolidated to registrable domain using Public Suffix List logic.

Public infrastructure exclusions

The published Article 23 source study excludes known navigation or infrastructure artifacts from public publisher analysis. The fresh child reconstruction is separately disclosed where its direct record-level citation count differs from the published source-study total.

Reddit identification

Reddit is identified at the registrable-domain level as reddit.com.

Citation-event share

Reddit citation-event share = Reddit citation events / all eligible public citation events

A response can contribute more than one Reddit citation event if multiple eligible Reddit URLs appear.

Response citation coverage

Reddit response citation coverage = eligible responses citing Reddit at least once / all eligible responses

Reddit counts no more than once per response for this metric.

Locked endpoint

The headline ChatGPT endpoint figures are preserved from Article 29, the parent financial Reddit trend study.

Locked matched prompt-plus-surface test

The headline matched panel is also inherited from Article 29. It contains 169 scenarios, with 7 both, 38 losses, 4 gains and 120 neither.

Vertical audit

The vertical table is recalculated directly from the frozen record-level corpus under the newer child-study implementation. It is reported separately from the locked parent endpoint.

Replacement-source audit

For fresh matched scenarios where Reddit appeared in July but not September, the analysis identifies registrable domains present in September but absent from the paired July citation set. Newly appearing domains can co-occur, so the table is not a mutually exclusive attribution model.

Limitations

1. The study covers one frozen three-month research window and should not be treated as a permanent ChatGPT rule.
2. Prompt sets are research panels, not search-volume-weighted market-share samples.
3. Visible citation does not prove recommendation causality, hidden retrieval influence or training-data use.
4. The study measures captured public-facing sources and cannot observe every internal retrieval step.
5. Vertical labels are source dataset labels and are not necessarily statistically independent markets.
6. Some smaller verticals have limited endpoint Reddit counts, so percentage changes can be volatile.
7. The parent matched panel and later child reconstruction use slightly different matching implementations. The published parent denominator is retained for cross-series consistency.
8. Article 23's public infrastructure filter produces a slightly smaller citation-event total than the later record-level reconstruction.
9. Newly appearing September domains are descriptive co-occurrences, not proven substitutes for Reddit.
10. Platform behavior can change after the research window.

Commercial Disclosure

LLM Authority Index is affiliated with CiteWorks Studio and related AI-search research and services. This research is designed to document observed AI citation behavior. Commercial relationships do not alter the frozen source corpus, eligibility rules, matching logic or published denominators.

No company can purchase a ranking, recommendation, score or position in this study. Citation visibility should not be interpreted as an endorsement by LLM Authority Index or by ChatGPT.

References

1. LLM Authority Index. The 2026 AI Citation Authority Study: Which Websites Does AI Cite for High-Stakes Decisions? https://llmauthorityindex.com/resources/research/2026-ai-citation-authority-study-high-stakes-consumer-decisions
2. LLM Authority Index. The Most-Cited Websites in AI for High-Stakes Investing, Retirement, Mortgage and Financial Consumer Decisions. https://llmauthorityindex.com/resources/research/most-cited-websites-ai-investing-retirement-mortgage-financial-high-stakes-consumer-decisions
3. LLM Authority Index. Reddit's Decline in AI Citations for High-Stakes Investing, Retirement, Mortgage and Financial Consumer Decisions. https://llmauthorityindex.com/resources/research/reddit-ai-citation-decline-investing-retirement-mortgage-financial-high-stakes-consumer-decisions
4. LLM Authority Index. The 100 Most-Cited Websites in ChatGPT for High-Stakes Investing, Retirement, Mortgage and Financial Consumer Decisions. https://llmauthorityindex.com/resources/research/top-100-chatgpt-citations-investing-retirement-mortgage-financial-high-stakes-consumer-decisions
5. LLM Authority Index. The Persistence-Portability Gap: Why AI Citation Authority Persists Over Time but Fragments Across Platforms. https://llmauthorityindex.com/resources/measurement/persistence-portability-gap
6. PromptWatch. Why Did ChatGPT Stop Citing Reddit? Inside the August 2026 Citation Collapse. https://promptwatch.com/blog/chatgpt-stop-citing-reddit
7. Search Engine Journal. Why Reddit's ChatGPT Citation Drop Isn't Fully Explained. https://www.searchenginejournal.com/why-reddits-chatgpt-citation-drop-isnt-fully-explained/586479/
8. Ahrefs. The 50 Most-Cited Websites in ChatGPT (September 2026). https://ahrefs.com/blog/most-cited-domains-in-chatgpt/
9. BrightEdge. Institution or Platform: What Health and Finance Citations Reveal About ChatGPT and Google AI Overviews. https://www.brightedge.com/resources/weekly-ai-search-insights/ai-overviews-chatgpt-authority-health-finance
10. Tinuiti. AI Citation Trends Report Q3 2026. https://tinuiti.com/research-insights/research/ai-citation-trends-report/

Related LLM Authority Index Research

Corpus foundation and measurement framework

• 2026 AI Citation Authority Study
• Overall Reddit Citation Decline Study
• Cross-Platform Citation Overlap Study
• AI Citation Drift Study
• Overall ChatGPT Top 100 Study
• Persistence-Portability Gap Framework

Investing, retirement, mortgage and financial source-market branch

• All-Platform Financial Citation Authority Study
• Google AI Overviews Financial Citation Sources
• Google AI Mode Financial Citation Sources
• ChatGPT Financial Citation Sources
• Perplexity Financial Citation Sources
• Gemini Financial Citation Sources
• Microsoft Copilot Financial Citation Sources

Financial Reddit-trend branch

• Financial Reddit Decline Parent Study
• Google AI Overviews Reddit Trend
• Google AI Mode Reddit Trend
• ChatGPT Reddit Trend
• Perplexity Reddit Trend
• Gemini Reddit Trend
• Microsoft Copilot Reddit Trend

Article 51 is the ChatGPT x Investing/Retirement/Mortgage/Financial x Reddit intersection study. The source-market branch explains the surrounding publisher ecosystem, the Reddit parent study supplies the locked cross-platform decline framework, and the five sibling Reddit studies show how the same source behaved on the other platform families.