Yep. All you need is what Baal said.
But even with the rubbers. If you have a pair and you are using them and you like them, if you don't play sanctioned tournaments where they check your rubber, who is going to bother you about it?
If you do play sanctioned tournaments that check your rubbers, then you would need to comply and change them.
So, do you play in scenarios where the currentness of ITTF approval matters? ITTF did approve those rubbers at some point. The rubbers have not changed. The only thing that has changed is that Addidas did not renew the approval by paying the ITTF fees.
If approval is just about paying fees, not too many people will care if you are using a rubber that used to be approved, was never ruled "illegal" but is no longer "legal" because the company no longer is in business.
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