¶2 Attorney Donald W. MacPherson appeals the Tax Court’s imposition of sanctions in two cases in which he counseled his taxpayer clients to maintain frivolous positions. We have jurisdiction pursuant to 26 U.S.C. § 7482(a)(1), and we affirm. Because the parties are familiar with the history of this case, we need not recount it here.
¶3 The Tax Court did not abuse its discretion in ordering MacPherson to pay excess costs pursuant to 26 U.S.C. § 6673(a)(2). See Grimes v. CIR, 806 F.2d 1451, 1454 (9th Cir. 1986) (standard of review). Mac-Pherson “multiplied the proceedings in [both cases] unreasonably and vexatiously.” 26 U.S.C. § 6673(a)(2). He “knowingly or recklessly raise[d] a frivolous argument.” Moore v. Keegan Mgmt. Co. (In re Keegan Mgmt. Co. Sec. Litig.), 78 F.3d 431, 436 (9th Cir. 1996). On behalf of his clients, he advanced a position contrary to established law and unsupported by fact. In a signed declaration, he represented that he knew his position would be unsuccessful. The Tax Court appropriately ordered MacPherson to pay only those costs incurred in responding to MacPherson’s frivolous arguments. See Moore, 78 F.3d at 435.
¶4 AFFIRMED.