Section 34.21 - General rule(a)Authorization. A national bank and its subsidiaries may make, sell, purchase, participate in, or otherwise deal in ARM loans and interests therein without regard to any State law limitations on those activities.(b)Purchase of loans not in compliance. Except as provided in paragraph (c) of this section, a national bank may purchase or participate in ARM loans that were not made in accordance with this part, provided such purchases are consistent with safe and sound banking practices as described in published OCC guidance, including appropriate diligence regarding the quality and characteristics of the loans, and other applicable regulations.(c)Purchase of loans from a subsidiary or affiliate. ARM loans purchased, in whole or in part, from a subsidiary or affiliate must comply with this part and with other applicable regulations, and be consistent with safe and sound banking practices as described in published OCC guidance, including appropriate diligence regarding the quality and characteristics of the loans. For purposes of this paragraph, the terms affiliate and subsidiary have the same meaning as in 12 U.S.C. 371c .61 FR 11300, Mar. 20, 1996, as amended at 73 FR 22251 , Apr. 24, 2008