I am grateful to Amanda Golden for letting me know the other day that Yale University's Beinecke Library has acquired two Plath family collections. The basic archival accession records are linked below. Main collection  (21 boxes) Addition  (2 boxes) There is not much to go on at this point in time, but the main collection includes "Correspondence, writings, photographs, printed material, artwork, personal papers, records, realia, and other papers by or relating to Sylvia Plath and the Plath family." And the addition has "Books, correspondence, photographic prints, audiovisual material, stamp collection, and other papers created by, or, related to Sylvia Plath and the Plath family." It may be a year or so before the collection is open to research; however, some parts will be closed until 1 January 2059. There are possibly other criteria that may allow for the closed materials to be made available. In addition to holding Sylvia Plath materials, there are likely d...