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Is there a NY tax form to use when one is missing a K-1 (or 1065) from an LLC?
Form 10-K is filed by corporations to SEC. You must be thinking of form 1065 (its schedule K) that a partnership (and multi-member LLC) must file with the IRS. Unless the multi-member LLC is legally dissolved, it must file this form. You're a member, so it is your responsibility, with all the other members, to make sure that the manager files all the forms, and if the manager doesn't - fire the manager and appoint another one (or, if its member managed - chose a different member to manage). If you're a sole member of the LLC - then you don't need to file any forms with the IRS, all the business expenses and credits are done on your Schedule C, as if you were a sole propriator.