Collaboration among L.A.’s top art institutions reached new heights Monday as the Hammer Museum, the Los Angeles County Museum of Art and the Museum of Contemporary Art announced the joint ownership and management of a collection of 260 works of art gifted by philanthropists Jarl and Pamela Mohn.

The collection — consisting entirely of works by L.A.-based artists — has been accumulated by the Mohns over the last two decades and is being called the Mohn Art Collective: Hammer, LACMA, MOCA, or MAC3.

The gift is accompanied by a $15-million to $20-million endowment for future acquisitions and is designed for annual growth. It also covers expenses incurred for storage and care of the art. “I don’t want it to be a burden,” Jarl Mohn told The Times about his decision to pair MAC3 with an endowment.

“I want this to be a really joyful experience and not a heavy lift for the institutions.” Mohn said the endowment is larger than “all the things I’ve supported at all the art institutions in L.A.

, in the aggregate over the last 20 years.” Mohn added that he wasn’t sure of the market value of the MAC3 collection, which was in the process of being appraised. He expected to know within the next four months.

The Hammer is augmenting the MAC3 collection with 80 works it has collected over the 12 years it has been staging its “Made in L.A.” biennials.

An additional 16 pieces have been added to the collection from “Made in L.A. 2023” by curators from all three mu.