ARTICLES, STUDIES, COMPLAINTS, POSTS, RESEARCH

• 21 Medicare Health Plans Warned To Fix Provider Directory Errors (KFF Health News, January 18, 2017): https://kffhealthnews.org/news/21-medicare-health-plans-warned-to-fix-provider-directory-errors/ – CMS warnings including Humana. 

• Online Provider Directory Review Report (CMS, January 31, 2018): https://www.cms.gov/medicare/health-plans/managedcaremarketing/downloads/provider_directory_review_industry_report_round_2_updated_1-31-18.pdf – CMS study from 2016-2018 on MA directory errors.
• X Post by Richard Smith (@richard17544320) on Humana Directory (November 1, 2018): https://x.com/richard17544320/status/1058040505525723136 – Complaint about inaccurate info for veterans.

No sources found for this year in the provided lists or additional searches.

• Incorrect Provider Directories Associated With Out-Of-Network Bills (Health Affairs, June 1, 2020): https://www.healthaffairs.org/doi/10.1377/hlthaff.2019.01501 – Study linking inaccuracies to higher out-of-network costs.
• Humana Targets Accuracy of Provider Directories (Becker's Payer, February 18, 2020): https://www.beckerspayer.com/payer/humana-targets-accuracy-of-provider-directories/ – Humana's CAQH partnership.
• Incorrect Provider Directories Associated With Out-Of-Network Mental Health Care And Outpatient Surprise Bills (PMC, September 2020): https://pmc.ncbi.nlm.nih.gov/articles/PMC7497897 – Study finding 53% of mental health directory users encountered inaccuracies, linked to higher out-of-network use and surprise bills.

• X Post by southpaw (@nycsouthpaw) on Specialist Billing Issue (June 8, 2021): https://x.com/nycsouthpaw/status/1402344714418982921 – Personal complaint about a provider listed in-network but billed out-of-network due to address error.
• Laying Ghost Networks to Rest: Combatting Deceptive Health Plan Provider Directories (Yale Law & Policy Review, 2021): https://yalelawandpolicy.org/laying-ghost-networks-rest-combatting-deceptive-health-plan-provider-directories – Analysis of state data showing failure of existing policies, proposing enforcement and fines to reduce errors.

• X Post by Tina Smith (@SenTinaSmith) on Ghost Networks (November 17, 2022): https://x.com/SenTinaSmith/status/1593289947250835457 – Description of common issues like wrong numbers or unavailable providers.
• X Post by drmaggiesa (@drmaggiesa) on Filing Complaints (September 30, 2022): https://x.com/drmaggiesa/status/1575641996655370240 – Advice on reporting inaccurate providers to state boards and insurers.

• Consistency of Physician Data Across Health Insurer Directories (JAMA, March 14, 2023): https://jamanetwork.com/journals/jama/fullarticle/2802329 – Analysis showing high inaccuracy rates across major insurers.
• Evidence on Inaccurate Directories Piles Up. It's Time to Act (AMA, May 18, 2023): https://www.ama-assn.org/health-care-advocacy/access-care/evidence-inaccurate-directories-piles-it-s-time-act – AMA report on 33% inaccuracy in provider listings.
• State Efforts to Coordinate Provider Directory Accuracy: Final Report (ASPE, December 27, 2023): https://aspe.hhs.gov/sites/default/files/documents/72a2324e3deb078b275c66eb53052c86/state-coordinate-provider-directory-accuracy.pdf – Report on state-level attempts to fix inaccuracies.
• Provider Directories Remain Inconsistent Despite No Surprises Act (Healthcare Dive, March 17, 2023): https://www.healthcaredive.com/news/inconsistent-physician-directories-no-surprises-act/645307/ – CMS review showing 5-93% errors.
• Inaccurate and Inadequate: Health Plan's Mental Health Provider Network Directories (New York AG, December 7, 2023): https://ag.ny.gov/sites/default/files/reports/mental-health-report_0.pdf – Report finding 86% of listed providers unreachable or not in-network.
• Majority Study Findings: Medicare Advantage Plan Directories Haunted by Ghost Networks Executive Summary (Senate Finance Committee, May 3, 2023): https://www.finance.senate.gov/imo/media/doc/050323%20Ghost%20Network%20Hearing%20-%20Secret%20Shopper%20Study%20Report.pdf – Secret shopper study revealing widespread inaccuracies in MA plans.
• Understanding Mental Health 'Ghost' Networks (Defacto Health, May 9, 2023): https://defacto.health/2023/05/09/understanding-mental-health-ghost-networks – Insights into how ghost networks affect mental health access.
• X Post by Ron Wyden (@RonWyden) on Ghost Networks (May 5, 2023): https://x.com/RonWyden/status/1654490394233651205 – Explanation of ghost networks and their dangers in insurer directories.
• Phantom Networks: Discrepancies Between Reported And Realized Mental Health Care Access In Oregon Medicaid (PMC, January 2023): https://pmc.ncbi.nlm.nih.gov/articles/PMC9876384 – Study finding 58.2% of directory listings were phantom providers in Medicaid, with higher rates in mental health.

• Characterizing Physician Directory Data Quality: Variation by Specialty (PMC, July 18, 2024): https://pmc.ncbi.nlm.nih.gov/articles/PMC11256460/ – Study on inconsistencies in health plan directories.
• Inaccuracies in Provider Directories Persist for Long Periods (PMC, June 4, 2024): https://pmc.ncbi.nlm.nih.gov/articles/PMC11195574/ – Research on the longevity of directory errors.
• State Regulators Know Health Insurance Directories Are Full of Errors (ProPublica, November 14, 2024): https://www.propublica.org/article/ghost-networks-health-insurance-regulators – Investigation into minimal enforcement and fines.
• Health Insurers' Provider Directories Still Riddled with Errors (Vital Record, July 10, 2024): https://vitalrecord.tamu.edu/errors-persist-health-insurer-provider-directories-despite-regulations-mandating-regular-updates/ – Persistence despite mandates.
• Inaccurate Provider Directories Create Barriers to Care (Availity, June 25, 2024): https://www.availity.com/blog/inaccurate-provider-directories-create-barriers-to-care-2/ – $3B annual spend yet high errors.
• Humana Taps Veda to Improve Accuracy of Provider Directories (Healthcare Finance News, February 27, 2024): https://www.healthcarefinancenews.com/news/humana-taps-veda-improve-accuracy-provider-directories – Veda partnership for real-time fixes.
• X Post by PERSIST! (@F_E_Wander) on Directory Inaccuracies (January 4, 2024): https://x.com/F_E_Wander/status/1742748927584264483 – Survey showing 53% mental health inaccuracies.
• The Hidden Costs of “Ghost Networks”: Addressing Provider Directory Challenges in Healthcare (Gaine, November 12, 2024): https://www.gaine.com/articles/the-hidden-costs-of-ghost-networks-addressing-provider-directory-challenges-in-healthcare – Discussion of data management issues, with 81% of entries inaccurate in major insurers per JAMA study.

• National Provider Directory Accuracy: July 2025 Report (Defacto Health, July 29, 2025): https://defacto.health/2025/07/29/national-provider-directory-accuracy-july-2025-report/ – Latest accuracy assessment, with only two payers at 70%.
• Patients Target Insurers in Suits Over Flawed Doctor Directories (Bloomberg, March 13, 2025): https://www.wagnerlawgroup.com/wp-content/uploads/sites/1101401/2025/03/031325BloombergArticleRCWQuote.pdf – Coverage of lawsuits over directory flaws.
• Beyond Broken Links: The High Stakes of Provider Directory Accuracy (MedCity News, July 6, 2025): https://medcitynews.com/2025/07/beyond-broken-links-the-high-stakes-of-provider-directory-accuracy-in-the-no-surprises-era/ – Regulatory context under No Surprises Act.
• $2.1 Billion Lost to Directory Errors: Here's a Smarter Way to Fix It (LinkedIn, April 22, 2025): https://www.linkedin.com/pulse/21-billion-lost-directory-errors-heres-smarter-way-4sixe – CMS finding 55%+ errors.
• Inaccuracies Related to Accepting New Patient Flags in Affordable Care Act Plans' Provider Directories (Health Affairs Scholar, May 2025): https://academic.oup.com/healthaffairsscholar/article/3/5/qxaf082/8113386 – Study highlighting errors in new patient acceptance flags exacerbating access issues.
• Harm to Medicare Advantage Enrollees From Directory Errors and Inadequate Networks (Medicare Rights Center, October 23, 2025): https://www.medicarerights.org/medicare-watch/2025/10/23/harm-to-medicare-advantage-enrollees-from-directory-errors-and-inadequate-networks – Report on how inaccuracies disguise inadequate networks, especially in behavioral health.
• ACA Network Regulatory Filings Are Inaccurate, Poorly Match Provider Directories (American Journal of Managed Care, September 16, 2025): https://www.ajmc.com/view/aca-network-regulatory-filings-are-inaccurate-poorly-match-provider-directories – Secret shopper survey revealing 65% inaccuracies in Pennsylvania ACA Marketplace listings.
• Many Medicare Advantage and Medicaid Managed Care Plans Have Limited Behavioral Health Provider Networks and Inactive Providers (OIG, October 7, 2025): https://oig.hhs.gov/reports/all/2025/many-medicare-advantage-and-medicaid-managed-care-plans-have-limited-behavioral-health-provider-networks-and-inactive-providers – Audit finding inactive providers and limited networks, recommending better monitoring.
• Washington Post Report Finds Errors in New Medicare Advantage Provider Directory (RISE Health, October 16, 2025): https://www.risehealth.org/insights-articles/washington-post-report-finds-errors-in-new-medicare-advantage-provider-directory – Investigation into duplicative and conflicting information in CMS's new directory tool.
• Persistence of Provider Directory Inaccuracies After the No Surprises Act (PMC, 2025): https://pmc.ncbi.nlm.nih.gov/articles/PMC12705072 – Research showing 45% of errors lasting beyond 90 days despite federal mandates.
• Errors In New Medicare Plan Portal Mislead Seniors On Coverage (J&R Report, October 16, 2025): https://jrreport.wordandbrown.com/2025/10/16/errors-in-new-medicare-plan-portal-mislead-seniors-on-coverage – Coverage of inconsistencies in the Medicare Plan Finder portal leading to misleading results.
• New Survey Reveals Healthcare Provider Directory Accuracy and Usability Hurdles (LexisNexis Risk Solutions, September 9, 2025): https://risk.lexisnexis.com/about-us/press-room/press-release/20250909-provider-directory-report – Survey finding 33% of users encounter outdated information and 21% face navigation difficulties.
• 'They delayed, they denied': How Insurance Errors Endanger California Patients (CalMatters, October 16, 2025): https://calmatters.org/health/2025/10/health-insurance-error-denial-ghost-network – Investigation into ghost networks causing delays and denials in care access.
• Ghost Network Lawsuits Mental Health Insurance | Provider Directory Fraud Claims (The Lyon Firm, December 29, 2025): https://thelyonfirm.com/blog/ghost-network-lawsuits-health-insurance-directory-fraud – Discussion of ongoing lawsuits over fraudulent directories in mental health coverage.
• “Ghost networks” Abound in Medicare Advantage and Medicaid, Research Shows (Lown Institute, December 2, 2025): https://lowninstitute.org/ghost-networks-abound-in-medicare-advantage-and-medicaid-research-shows – Analysis of network violations due to insufficient or inaccurate provider listings.
• Ghost Networks & Claim Denials (Gianelli & Morris, June 26, 2025): https://www.gmlawyers.com/ghost-network-insurance-denial – Legal perspective on bad faith denials linked to inaccurate directories.
• X Post by My American Dream #CrushedByHealthInsurers (@MakeHCFairAgain) on Maternity Case (November 3, 2025): https://x.com/MakeHCFairAgain/status/1985191571646492927 – Story of high-risk pregnancy impacted by Anthem's ghost network.
• X Post by HealthCareDenied (@CareDenied) on Open Enrollment Warning (October 21, 2025): https://x.com/CareDenied/status/1980767005960724911 – Alert about choosing plans with ghost networks during enrollment.
• X Post by Sandy Eggo (@Fronterakid) on California Investigation (October 21, 2025): https://x.com/Fronterakid/status/1980598344411202000 – Link to report on insurance errors and ghost networks endangering patients.
• X Post by Insurance Law News (@Insurance_Alert) on ERISA Settlement (September 26, 2025): https://x.com/Insurance_Alert/status/1971567710858600578 – Update on ghost network class action lawsuit settlement.
• X Post by Insurance Law News (@Insurance_Alert) on NY Fine (September 8, 2025): https://x.com/Insurance_Alert/status/1965089524566069608 – Report on $250,000 fine for mental health ghost network.
• X Post by Insurance Law News (@Insurance_Alert) on NY AG Action (August 29, 2025): https://x.com/Insurance_Alert/status/1961445029584802166 – Coverage of AG putting mental health ghost network to rest.
• X Post by Center for Health and Democracy (@cforhd) on Ghost Networks (July 10, 2025): https://x.com/cforhd/status/1943319971557445844 – Discussion of calling around without responses due to inaccurate directories.
• X Post by M M Insurance Agency (@MMins) on Avoiding Ghost Networks (July 3, 2025): https://x.com/MMins/status/1940712146230255785 – Tips on avoiding ghost network issues in health plans.
• Understanding and avoiding "ghost networks" (Ensora Health, July 23, 2025): https://ensorahealth.com/blog/understanding-and-avoiding-ghost-networks – Overview of inaccurate directories listing unavailable providers and tips to avoid them.

• Building a Reliable National Provider Directory—Lessons From Other Sectors (JAMA Health Forum, 2026): https://jamanetwork.com/journals/jama-health-forum/fullarticle/2839910 – Discussion on high inaccuracy rates and lessons from other industries for improvement.
• American Psychiatric Association Files Class Action Complaint Against EmblemHealth, Inc. (APA, January 8, 2026): https://www.psychiatry.org/news-room/news-releases/apa-class-action-complaint-against-emblemhealth – Lawsuit alleging ghost networks force out-of-network care and higher costs.
• The “Ghost Network” Problem: The Key Questions Employers Can Ask to Avoid Little-Known Benefits Risk (Fisher Phillips, January 5, 2026): https://www.fisherphillips.com/en/news-insights/the-ghost-network-problem.html – Guidance for employers on identifying and avoiding ghost networks in benefits plans.
• X Post by Wolf Popper LLP (@WolfPopperLLP) on Out-of-Network Surprises (January 30, 2026): https://x.com/WolfPopperLLP/status/2017309325157445758 – Call for experiences with providers listed in-network but billing as out-of-network.
• X Post by Mark Payne (@Mark_Paynewrite) on Anthem Lawsuit (January 27, 2026): https://x.com/Mark_Paynewrite/status/2016236103850725612 – Coverage of lawsuit alleging inaccurate mental health directories.
• X Post by Jon Lebkowsky (@jonl) on Complaint Filing (January 24, 2026): https://x.com/jonl/status/2015159844760612876 – Recommendation to complain to state departments about access issues.
• X Post by inseparable (@IAmInseparable) on Utah Legislation (January 26, 2026): https://x.com/IAmInseparable/status/2015864706099994886 – Update on bill to address ghost networks with accountability measures.
• X Post by HealthCareDenied (@CareDenied) on Blue Shield Lawsuit (January 5, 2026): https://x.com/CareDenied/status/2008323347000541673 – Highlight of lawsuit over unreachable mental health providers in directories.
• X Post by ObserverWithout (@ObserverWithout) on Address-Stacking (January 24, 2026): https://x.com/ObserverWithout/status/2015197412692811946 – Discussion of address-stacking in registries enabling improper payments, per HHS audits.

• The Hidden Causes of Inaccurate Provider Directories (CAQH, Undated): https://www.caqh.org/hubfs/43908627/drupal/explorations/CAQH-hidden-causes-provider-directories-whitepaper.pdf – Whitepaper on administrative burdens causing errors.
• How the No Surprises Act Affects Provider Directories (ProviderTrust, Undated): https://www.providertrust.com/blog/how-the-no-surprises-act-affects-provider-directories/ – Explains regulatory impacts on directories.
• How Inaccurate Health Plan Provider Directories Block Access to Care (Families USA, Undated): https://familiesusa.org/resources/how-inaccurate-health-plan-provider-directories-block-access-to-health-care/ – Discusses timelines for corrections.
• Ghost Networks in Healthcare: The Crisis of Phantom Provider Directories (WCHSB, Undated): https://wchsb.com/wch-news/ghost-networks-in-healthcare-the-crisis-of-phantom-provider-directories – Overview of how inaccuracies harm patients and providers, especially in mental health.
• What are Ghost Networks in Healthcare: An Overview (Quest Analytics, Undated): https://questanalytics.com/news/what-are-ghost-networks – Explanation of phantom providers and their impact on patient access.
• Ghost Networks: Inaccurate Healthcare Provider Directories (Kozyak Tropin & Throckmorton, Undated): https://kttlaw.com/ghostnetworks – Investigation into directories listing unavailable providers, leading to delays and out-of-network costs.