Philadelphia-based Dolchin, Slotkin & Todd, a 40-year-old law firm focused on business transactions and litigation, is closing, according to three partners who are moving to a larger firm.

In interviews, tax, trust and estates attorneys Zachary Dolchin, Wendy Cooper and Stephen Frishberg said they are moving to Semanoff Ormsby Greenberg & Torchia after the closing of their prior firm, Dolchin Slotkin. They said the 12-attorney firm shuttered its offices at the end of June following the retirement of managing shareholder and firm founder Jerry Dolchin, who did not respond to requests for comment. (Zachary Dolchin is Jerry Dolchin’s son.)