In an arbitration claim seeking more than $50 million in damages, advisor Sam Su is accused of telling a client “that to withdraw money from her accounts, she would have to engage in sexual relations with him.”
A former wirehouse advisor has been accused of abusing his role as a fiduciary to further a sexual relationship with a client and compel her to recruit other clients on his behalf.
A statement of claim filed Thursday in the Financial Industry Regulatory Authority‘s dispute-resolution system accuses San Francisco–based advisor Sam Su of assault, sexual battery and sexual harassment during a long-running extramarital affair with a client. The claim also names two of Su’s former employers, UBS and Morgan Stanley.
The relationship is alleged to have begun in or around 2016, when Su was at UBS. The client, whose full name was not disclosed to FA-IQ, claims that Su began making advances at a time when she was experiencing severe depression, anxiety and post-traumatic stress disorder stemming from difficult divorce proceedings, according to the statement of claim.
Su, who was married at the time, began inviting the client to client-appreciation events in destinations such as Las Vegas, the statement of claim asserts. “These blurred the lines between professional and personal, leaving [the client] confused and reliant on Su for financial guidance,” according to the filing.
The client claims that “unwanted sexual advances and inappropriate physical contact” by Su eventually “became a normalized yet profoundly inappropriate part” of their business interactions, and she claims that she occasionally “felt pressured to comply with Su’s demands for sexual relations.”
She also claims that Su, in his conversations with her, disclosed confidential information about other clients. Su did not respond to an email and a phone call seeking comment on Friday.
Su voluntarily left UBS for Morgan Stanley in 2023, according to his CRD Snapshot report maintained by state regulators, and he persuaded the client to move her account there, the statement of claim asserts.
Su thereafter “escalated his inappropriate demands for sex, taking advantage of [the client’s] fragile state of mind,” the statement of claim asserts. Su also convinced the client “that to withdraw money from her accounts, she would have to engage in sexual relations with him,” according to the filing.
Later, when the client was unemployed and concerned about her finances, Su told her that she “needed to ‘sex him up’ in exchange for ‘taking care of [her] finances,'” according to the statement of claim.
The client also claims that Su told her that she would have to provide him new clients to remain in his “good graces” and receive an “allowance” from her investment accounts.
Su was discharged by Morgan Stanley on Jan. 13 of this year, according to his CRD Snapshot. The firm in its Form U5 filing indicated that the separation stemmed from a “[l]oss of confidence due to concerns about engagement with personnel in violation of Firm human resources policies.” The issue was not related to sales practices, clients or securities, the firm added.
After Su’s departure from Morgan Stanley, the client discovered that her account had been invested speculatively and overconcentrated — with 80% in Tesla stock — and that she had been issued a bank loan of more than $200,000 at an interest rate of nearly 10%, according to the statement of claim. The investments were not aligned with the client’s objectives and risk tolerance, the filing asserts.
The client claims that she eventually disclosed the details of her relationship with Su to his replacement at Morgan Stanley and was told by that advisor that the firm was aware of Su’s conduct and that Su had sexually harassed other women. According to the statement of claim, the advisor also asked the client if Su had ever drugged her.
The client claims that she has reported Su’s conduct to UBS and Morgan Stanley. Against Su and the two wirehouses, her claim asserts formal allegations of sexual harassment in a professional relationship, sexual battery, assault, intentional infliction of emotional distress, breach of fiduciary duty, fraud through intentional and negligent misrepresentation, breach of oral and written contracts, and violation of state and federal securities laws, Finra rules of fair practice, and New York Stock Exchange rules.
She also alleges that UBS and Morgan Stanley failed to supervise and control Su, though the statement of claim does not allege specific supervisory lapses beyond overlooked “red flags.” She is seeking compensatory damages of at least $50 million in addition to punitive damages, recission of unsuitable investments, recovery of legal fees and costs, and interest.
Spokespersons for UBS and Morgan Stanley declined to comment.
“When an advisor of a firm has a professional relationship with a customer, they breach their professional ethics and betray the client by engaging in the alleged behavior,” the claimant’s attorney, David Harrison, told FA-IQ in an emailed statement.
“We are investing Mr. Su’s conduct and have reason to believe that the customer we represent is not the only victim,” added Harrison, of Studio City, California–based Bakhtiari & Harrison, which represents customers in claims involving the financial services industry.
Su has been registered at Ameriprise since February. The claim does not include any allegation related to Su’s tenure at that firm. An Ameriprise spokesperson told FA-IQ that “Mr. Su did not disclose any information pertaining to these allegations when he joined Ameriprise in February 2025.”
“While the alleged actions occurred prior to his joining Ameriprise, we are investigating further,” the spokesperson said via email, adding that the firm “is committed to fostering a workplace centered on integrity and free of discrimination and harassment of any kind.”
Su’s career dates to 2000, when he registered at Merrill Lynch. He moved to Morgan Stanley nearly two years later, returned to Merrill in 2005 and joined UBS in 2008, according to his CRD. His record does not include any customer complaints or other disclosures, and aside from this year’s departure from Morgan Stanley, his departure from each firm was termed “voluntary,” per his CRD.