"The research by Prof Maguire and Dr Emma Smith, from Oxford University's English faculty, suggests that the playwright Thomas Middleton, a contemporary of Shakespeare's, appears to be the likely candidate.At least it's a co-author. The last thing we'd need is for something to fall from the canon at this late stage. I hope the Arden edition isn't close to completion.
"Writers have their own distinctive literary "fingerprints" - a kind of stylistic DNA - and a highly-detailed analysis of the language in the play shows "markers" strongly linked to Middleton.
"The rhyming and rhythms of sections of the play, the phrasing, spelling and even individual words suggest the involvement of Thomas Middleton."
All's Well That Ends Well may have been co-authored by Thomas Middleton according to Oxford scholars: