Steely Dan co-founder Donald Fagen has filed a lawsuit against the estate of his late bandmate Donald Fagen in an attempt to maintain his control of the band as an entity, Rolling Stone reports.

Becker passed away in early September, and Fagen suit explains that he received a note from his parter’s estate regarding a Buy/Sell Agreement that the two signed in 1972. The contract outlined what would happen in the event of one of the band members either quitting the band or dying, in which case that member’s shares of the band would be purchased by the remaining members.

Becker’s estate is now claiming that the 1972 Buy/Sell Agreement “is of no force or effect,” and the letter sent to Fagen reportedly stipulated that Becker’s widow Delia was due 50 percent ownership of Steely Dan and should be appointed a director of the band going forward.

Fagen, for his part, has brought the lawsuit against Becker’s estate to enforce the Buy/Sell Agreement and retain control of the band he founded, noting in the suit that Becker “reaffirmed his commitment” to the contract in 2009.

“Fagen – acting on behalf of himself and on behalf of Steely Dan, as its sole remaining officer and director – hereby exercises the mandatory provision of the Buy/Sell Agreement requiring Steely Dan to purchase Becker’s shares,” the lawsuit explains, also claiming that Becker’s estate has already begun to take undue control of Steely Dan’s properties, including the band’s website. “This lawsuit is required for Steely Dan and Fagen to obtain a judicial determination that Becker’s shares must be sold to Steely Dan pursuant to the express terms of the Buy/Sell Agreement, so that Steely Dan and Fagen can go on as contemplated and provided by the Buy/Sell Agreement.”