- 2016: Berkshire Museum trustees use two board retreats to discuss institution's future, including possible sale of artworks. Museum files new corporation papers with the Secretary of State's Office. Using language taken directly from state law, the organization says, among other things, that it holds the right to "sell, convey, lease, exchange, transfer or otherwise dispose of all or any of its property ...."

- Spring 2017: Museum board authorizes its president, Elizabeth McGraw, and museum Executive Director Van Shields to sign consignment contract with Sotheby's for 40 works of art, which they do in June.

- June 22: Museum attorney Mark Gold notifies attorney general in a letter of plan to sell 40 works of art from collection, saying none of the works is under restriction. He says auction proceeds could be as high as $75 million.

- July 11: Museum's Collections Committee meets to change its policies, eliminating a requirement that it first offer works being culled from its holdings to other museums and allowing it to use sale proceeds for operations expenses. Committee votes to approve deaccession of 40 works; minutes released by museum show no discussion of issue.

- July 12: Museum officials announce plan to sell 40 works from the collection and use proceeds to build an endowment to ensure financial stability and to pursue building renovations related to its "New Vision" project to emphasize multimedia and interactive exhibits focusing on science and natural history.

- Late July: Three national museum groups oppose plan to use auction proceeds for project and endowment. They include the Association of Art Museum Curators, the Association of Art Museum Directors and the American Alliance of Museums.

- Sept. 5: Van Shields confirms that he had withdrawn the museum's relationship with the Smithsonian Institution. The two had been affiliated since April 2013.

- Sept. 20: Massachusetts Cultural Council asks museum leaders to halt sale of artworks; group suspends its fiscal year 2018 funding to museum. Council's executive director, Anita Walker, calls museum's plan a "violation" of the public trust.

- Sept. 22: State Rep. Tricia Farley-Bouvier, D-Pittsfield, backs museum's planned art sale and the people who shaped it, saying, "I stand firmly with the board of the Berkshire Museum."

- Sept. 25: Nancy Edman Feldman resigns from museum board at its annual meeting. Departure follows departure in August of Carol Riordan, who had abstained from the July 12 vote to sell art. "I resigned because I didn't agree with the strategic direction the museum was taking," said Riordan, the board's treasurer. "I didn't find it transformative."

- Oct. 13: Pittsfield Mayor Linda Tyer said she supports museum's "bold transformation" to an institution focusing on science and natural history.

- Oct. 20: Group of plaintiffs, including three sons of artist Norman Rockwell and Pittsfield artist Tom Patti, files a civil lawsuit seeking an injunction halting the sale. Suit names attorney general as a part of interest, compelling that office to file a response.

- Oct. 20: Sotheby's devotes 33 of 188 pages in an online catalog to the first sale of works linked to the museum's New Vision project. Sotheby's schedules show that only 19 of original 40 works have scheduled sale dates.

- Oct. 24: Shields, the museum's executive director, begins a medical leave for surgery on a heart valve and will be absent through rest of year, museum announces. Nina Garlington and Craig Langlois will act as co-executive directors during Shields' absence.

- Oct. 26: Second group of plaintiffs, made up of three residents of Lenox, files suit in Suffolk Superior Court also seeking injunction; the cases are combined.

- Oct. 27: New England Museum Association holds "think tank" called "The Deaccessioning Dilemma: How Can We Support Standards AND Museums in Crisis?"

- Nov. 1: Judge John A. Agostini of Berkshire Superior Court holds a hearing on the combined cases. Near end of hearing, the lead lawyer for the state asks that, if plaintiffs are found to lack standing, it be entered as a plaintiff.

- Nov. 7: Agostini denies request for injunction and criticizes attorney general for handling of its review of the deaccession and sale.

- Nov. 10: Attorney general seeks and secures preliminary injunction from Massachusetts Appeals Court. The 30-day order bars the art sale, forcing seven Berkshire Museum works to be pulled from a scheduled Nov. 13 auction in New York City. Other works are also removed from three other auctions that week.

- Nov. 20: State Sen. Adam Hinds, D-Pittsfield, praises museum trustees for taking bold action but says they might need to consider compromise; urges parties to find common ground.

- Nov. 20: Justice Joseph A. Trainor clarifies that all proceedings in Berkshire Superior Court are on hold.

- November and early December: The museum and sale opponents file multiple motions with the Massachusetts Appeals Court. The museum seeks speedy trial at the Superior Court level. Opponents back higher-court review.

- Dec. 13: Trainor extends injunction through Jan. 29. "These delays benefit no one," said William F. Lee of the Boston law firm WilmerHale. "It is ironic that, during this holiday season when the museum is visited and enjoyed by more families than ever, its future is placed in grave jeopardy."

- Dec. 18: Appeals Court does not grant the museum's request to lift the prohibition on Superior Court action. It also denies the museum's bid to expedite the appeal, which normally takes many months to more than a year to play out.

- Dec. 26: Shields returns from his medical leave on a part-time basis.

- Ahead: On or before Wednesday, the Attorney General's Office is due to file a status report to the Appeals Court on its investigation.