Once the tax debt is paid in full, settled through an Offer in Compromise, or discharged through bankruptcy, the IRS must release the lien within 30 days. The IRS will also file a Notice of Release of Federal Tax Lien, which clears the public record and confirms that the lien is no longer in effect.
If the tax lien is released due to the collection statute expiring, then the IRS will do nothing as any NFTL already states on it the expiration date and statement of being self-released.