As Berkshire Hathaway marks Warren Buffett ‘s official retirement Wednesday, attention is shifting to a less settled part of the succession plan: the fate of its $300 billion equity portfolio. For decades, Berkshire’s stock holdings have reflected Buffett’s long-term investing judgment and his willingness to deploy capital aggressively during market turmoil. With no obvious successor possessing a comparable record in public equities, some analysts say Berkshire may ultimately scale back active stock selection, particularly given the size and concentration of the portfolio. “At some point the shoes are just too big to fill,” said Deiya Pernas, an analyst at Pernas Research. “He’s made some enormously large and tactical decisions. I don’t think that there’s going to be somebody who’s going to be able to make those types of decisions.” Buffett has said that Greg Abel , Berkshire’s new CEO effective this week, will make capital allocation decisions , a remit that includes the equity portfolio. Abel, a longtime operator who rose through Berkshire’s energy business, is widely respected inside the company. But he has not built a public track record as a stock picker, leaving some shareholders uneasy about whether Berkshire can continue to manage one of the world’s largest — and most concentrated — equity books without its legendary steward. Those concerns have intensified following the departure of Todd Combs, one of two longtime investment managers once seen as potential heirs to Buffett’s investing role. Near-term oversight is likely to fall to Abel with support from Ted Weschler, one of Berkshire’s remaining investment managers, but that structure could face scrutiny if the investment bench thins further, according to CFRA’s Cathy Seifert. “If Ted decides to leave, my sense is investors are likely to push for additional investment management or oversight — either internally or externally,” said the Berkshire analyst. David Kass, a finance professor at the University of Maryland and a Berkshire shareholder, raised the question whether Berkshire will hire more managers to distribute responsibility. “Will Greg hire one or more people to work with Ted Weschler? Will Greg actually pick stocks? Will he make decisions to sell? I believe Ted and others to be hired are likely to manage the portfolio,” he said. Berkshire has been aggressively trimming its two largest equity holdings — Apple and Bank of America — paring positions that for years defined the portfolio. Apple alone had grown to account for roughly half of Berkshire’s equity book at its peak, while Bank of America has long been one of Buffett’s highest-conviction financial bets. The sales have boosted Berkshire’s cash pile and reduced concentration risk. Others argue that Berkshire could retain equity exposure while reducing the burden of active management. Meyer Shields, a managing director at Keefe, Bruyette & Woods, said the company would be better off holding broad market indexes, particularly as outperforming benchmarks becomes more difficult at Berkshire’s scale. “It’s understandably very difficult to outperform broader indices with a portfolio of Berkshire’s size, and it’s probably just not worth the incremental effort and expense,” Shields said. “I do assume Berkshire still wants to invest in equities to leverage the float. I just think that all of the reasons for holding indices (which Buffett has laid out in the past) also make sense for Berkshire.” Pernas expects any shift to play out gradually. Rather than a wholesale change, he sees Berkshire continuing to sell down pieces of the portfolio over time, allowing public equities to fade as a defining feature of the company. “Maybe in 10 or 15 years,” he said, “they hope everybody kind of just forgets about it.”