From PSA's most recent 10-Q (qtr ended 3/31/19), pg 11
https://q10k.com/CLCT
Warranty Costs
We provide a limited warranty covering the coins and trading cards that we authenticate and grade. Under the warranty, if any collectible coin or trading card that was previously authenticated and graded by us is later submitted to us for re-grading and either (i) receives a lower grade upon that re-submittal or (ii) is determined not to have been authentic, we will offer to purchase the collectible or, in the alternative, at the customer’s option, pay the difference in value of the item at its original grade, as compared to its value at its lower grade. However, this warranty is voided if the collectible, upon re-submittal to us, is not in the same tamper-evident holder in which it was placed at the time we last graded it. We accrue for estimated warranty costs based on historical trends and related experience. We monitor the adequacy of our warranty reserves on an ongoing basis for significant claims resulting from resubmissions receiving lower grades or deemed not to have been authentic. Warranty expense recognized in the three and nine months ended March 31, 2019 was $73,000 and $402,000, respectively, as compared to $128,000 and $343,000, respectively, in the three and nine months ended March 31, 2018.
Also from that same 10-Q page 12
Their accrued warranty reserve at the end of 3/31/19 looks to be $728,000.