FINRA Bars Florida Broker Mark Frederic Seruya for Withholding Documents During OBA Investigation

FINRA holds brokers to strict standards of transparency and cooperation, especially during active investigations. When those standards are ignored, disciplinary action can follow.

Mark Frederic Seruya (CRD #1108375), a former financial advisor based in Sunny Isles, Florida, was permanently barred in March 2025 after refusing to provide documents and information requested during a Financial Industry Regulatory Authority (FINRA) investigation. The case, filed under FINRA Case #2024083143001, followed Seruya’s separation from Morgan Stanley amid concerns over undisclosed outside business activities (OBAs) and the use of unauthorized communication methods.

Sonn Law Group is now investigating Seruya’s conduct and is offering free consultations to investors who may have worked with him or been affected by related misconduct.

FINRA Cites Serious Compliance Violations in March 2025 Bar

According to the Letter of Acceptance, Waiver and Consent (AWC) finalized on March 27, 2025, FINRA barred Seruya after he refused to comply with requests for documents and information under FINRA Rule 8210. His failure to cooperate also violated Rule 2010, which governs standards of ethical conduct in the securities industry.

The investigation stemmed from a Form U5 submitted by Morgan Stanley in July 2024, reporting that Seruya had been permitted to resign following an internal review. That review found:

• Seruya participated in outside business investments involving firm clients.
• He resolved at least one dispute involving a client and an outside business investment.
• He used a non-approved messaging platform to conduct firm-related business communications.

These actions raised multiple compliance concerns, particularly relating to oversight, transparency and adherence to firm policies on OBAs and electronic communications. Seruya’s refusal to cooperate with FINRA’s inquiry ultimately led to his permanent bar from the industry.

Prior Disclosures and Regulatory Issues

Seruya’s professional record reveals a series of disclosures that span decades and raise concerns about his history in the financial services industry. According to FINRA records, Seruya has been the subject of two customer disputes, a criminal charge and a termination linked to compliance concerns.

• In 1999, Seruya and co-respondents were found jointly liable in a FINRA arbitration case involving Bear Stearns. The dispute alleged a fraudulent options scheme tied to a third-party individual. The claim resulted in a $1.375 million award to the claimants, with Seruya personally contributing nearly $378,000.
• An earlier complaint from 1991 led to a $60,000 settlement. The claim involved misrepresentation and supervision failures related to an options strategy with LMG Asset Management.
• Seruya also has a criminal disclosure stemming from a 1978 petty larceny conviction involving a minor theft and a $25 fine.

These prior disclosures compound the seriousness of the issues cited in Seruya’s eventual bar from the industry and underscore a broader pattern of regulatory and client-facing concerns.

Outside Business Activities and Red Flags

Seruya’s termination from Morgan Stanley followed an internal review of his involvement in multiple OBAs, several of which reportedly included firm clients. These OBAs included real estate investments in entities such as Windsor Gardens and Northside Plaza, along with student housing ventures and other holdings across Ohio and New Jersey.

According to FINRA Rule 3270, brokers must disclose and obtain firm approval for all OBAs, particularly those that may involve firm clients or create conflicts of interest. Seruya’s failure to do so was cited directly in his Form U5 and played a central role in the ensuing regulatory investigation.

Further compounding the issue, Seruya was found to have used non-firm-approved messaging platforms to conduct firm business. Unauthorized communication channels limit supervisory oversight and are a growing focus of enforcement by both FINRA and the SEC.

Ultimately, Morgan Stanley permitted Seruya to resign in July 2024 after uncovering these compliance failures, including the resolution of a dispute involving one of his outside investments with a firm client.

Seruya’s Broker History and Certifications

Seruya began his brokerage career in 1983 and maintained registrations with several major firms over four decades. His most recent affiliation was with Morgan Stanley from 2009 until his separation in 2024. Prior to that, he was registered with Morgan Stanley & Co. Inc. (2008-2009) and spent over 20 years at Bear Stearns (1985-2008), where many of his disclosed customer disputes originated.

Throughout his career, Seruya passed several securities qualification exams, including the Series 3, Series 7, Series 63, Series 65 and Securities Industry Essentials (SIE).

Why This Matters for Investors

Financial advisors are expected to follow clear compliance protocols to protect clients and maintain trust in the financial system. When brokers engage in OBAs involving clients, especially without firm disclosure, they may be creating undisclosed conflicts of interest that compromise investor protection.

Likewise, using unofficial messaging platforms for business communication can bypass firm oversight and allow problematic behavior to go undetected. Seruya’s refusal to cooperate with FINRA’s investigation raises further concern, as it may signal attempts to obscure misconduct or avoid accountability. When an advisor violates these standards, it puts investor funds and confidence at risk.

Warning Signs for Investors

Unapproved outside business activity and off-platform communication are common red flags in broker misconduct cases. Investors should be on alert if they notice any of the following:

• Private investment pitches that are not part of the brokerage firm’s official offerings.
• Business conducted through non-firm channels, such as WhatsApp, Signal or personal email addresses.
• Evasive or unclear communication, especially when requesting documentation or explanations about transactions.
• Sudden advisor departure from a firm without a clear reason or follow-up from the brokerage.

If you’ve encountered any of these behaviors, it may be time to consult a securities attorney to evaluate whether your rights have been compromised.

Speak With a Securities Attorney at Sonn Law Group

If you invested with Mark Frederic Seruya and have concerns about undisclosed business activity, off-platform communication or unresolved disputes, it’s important to have your situation reviewed. These behaviors may signal broader regulatory violations or misconduct that could impact your financial interests.

Sonn Law Group represents investors nationwide in claims involving financial advisor negligence, failure to supervise and violations of FINRA rules. We handle cases on a contingency fee basis, meaning you won’t owe anything unless we recover compensation for you.

To schedule a free, confidential consultation, call us at 833-912-3000 or fill out our online contact form.