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26 U.S. Code § 6063 - Signing of partnership returns

The return of a partnership made under section 6031 shall be signed by any one of the partners. The fact that a partner’s name is signed on the return shall be prima facie evidence that such partner is authorized to sign the return on behalf of the partnership.

(Aug. 16, 1954, ch. 736, 68A Stat. 748.)