From the directv customer agreement:
"(e) Access Card. You have received a conditional access card (referred to as the "Access Card") and a License Agreement governing your use of the Access Card while you are receiving our Service. Access Cards are nontransferable and are the exclusive property of DIRECTV. If you tell us that the original Access Card was lost, damaged, defective or stolen, we will replace it, as long as there is no evidence of unauthorized tampering with or modification of the Access Card and your account is in good standing. A replacement fee may apply (described in Section 2). Tampering with or other unauthorized modification of the Access Card is strictly prohibited and may result in criminal or civil action. Tampering with or inserting any device into your receiver other than an authorized unmodified Access Card is prohibited. DIRECTV reserves the right to cancel or replace the Access Card. Upon Request, the card must be returned to DIRECTV. If you do not return the Access Card to DIRECTV when you cancel your Service, you may be charged a fee as described in Section 2. Requesting Access Cards on behalf of other persons or for purposes other than lawful viewing of DIRECTV Service is prohibited."
The fee section says "(2) Up to $300 Access Card Replacement Fee, if you lose or fail to return your Access Card"
I guess directv is a little inconsistent about this policy. I have several old directivo's and an SD directv receiver. When I was going to reactivate the directivo's, I was told that I could not use the old access cards or the one from the other receiver, and would need to pay $20 a pop for new ones.