In 2024, his longtime interpreter, Ippei Mizuhara was accused of stealing $17 million from Ohtani’s personal bank account to pay illegal gambling debts. Prosecutors later revealed Mizuhara had impersonated Ohtani more than two dozen times to authorize wire transfers. Mizuhara has been sentenced to five years in prison. Though Ohtani was fully exonerated, the case exposed a core vulnerability shared by many high-net-worth individuals: When one trusted insider has too much access and too little oversight, even the most successful, well-advised person can be left exposed. Comerica shares five lessons to learn from Shohei Ohtani’s story.
In 2024, Ohtani signed a $700-million contract with the Dodgers, setting a new record for professional sports in North America.
For years, Ippei Mizuhara was far more than Shohei Ohtani’s interpreter. He coordinated travel, handled media, managed daily logistics, and even sat in on meetings with Ohtani’s financial advisors. The level of access blurred professional boundaries. Over time, it gave Mizuhara visibility into nearly every part of Ohtani’s life, including enough authority to quietly manipulate banking details without detection.
Lesson: Don’t let one person sit at every intersection of your personal and financial life. Divide responsibilities among separate professionals — for example, a business manager, CPA and personal assistant — and make sure every key decision involves more than one set of eyes.
Mizuhara was a trusted confidant, not a licensed fiduciary.
He helped Ohtani open his personal bank account in 2018 and later used that access to impersonate him in more than two dozen phone calls. Those conversations authorized wire transfers that moved $17 million out of Ohtani’s account and into the hands of an illegal bookmaker.
With professional oversight, those transfers would have hit a wall. A licensed fiduciary would have required written approval, dual verification and full documentation. Alerts would have reached multiple parties, and the unusual activity would have been stopped before it ever left the account.
Lesson: Anyone with authority over your money should be vetted, credentialed and bound by fiduciary duty. Use licensed professionals or a corporate trustee for money movement, and maintain dual authorization for all wire transfers and large payments. Once funds are stolen, recovery, through insurance or restitution, is rarely complete.
Professional fiduciaries use built-in safeguards like dual authorization, multi-factor verification and independent alerts that make large unauthorized transfers nearly impossible.
One of the simplest steps in Mizuhara’s scheme was also the most damaging: He changed Ohtani’s contact information. By rerouting verification calls and email alerts to himself, he was able to move millions of dollars without triggering suspicion.
Even small administrative changes like these can open the door to major financial losses, especially when no one is checking the details.
Lesson: Keep direct, personal access to all your accounts. Require banks and custodians to send duplicate alerts to you and an independent advisor. Schedule regular reviews at least quarterly to confirm every transfer and withdrawal.
As Ohtani’s career expanded, so did his financial footprint, spanning countries, contracts and an entire team of advisors and staff. But his financial oversight didn’t evolve at the same pace. A structured audit would likely have caught irregular activity early, especially as Mizuhara’s responsibilities expanded beyond translation into areas that touched travel, logistics and financial communication.
Lesson: Schedule independent financial reviews every one to two years. These check-ins confirm who has access to accounts, how transactions are authorized and whether outdated permissions or gaps exist.
When news first broke, headlines momentarily linked Ohtani’s name to illegal gambling operations. For days, the world’s biggest sports media outlets speculated about his involvement. Prosecutors later confirmed he was a victim, not a participant, but the damage control required global coordination between his legal, media and advisory teams.
High-profile individuals face similar risks. Once public perception takes shape, even unfounded allegations can erode trust, unsettle business partners and impact long-term brand value.
Lesson: Treat reputation management as part of your financial plan. Keep meticulous records of fiduciary oversight and decision-making. Also, establish clear communication protocols for crisis response and make sure your advisors can act quickly to protect your wealth and your name.
This story was produced by Comerica and reviewed and distributed by Stacker.