Minn. Stat. § 514.71: RELEASE.

No release of such causes of action, or any of them, or of any judgment thereon shall be valid or effectual as against such lien unless such lienholder shall join therein, or execute a release of such lien, and the claimant, or assignee of such lien, may enforce such lien by action against the person, firm, or corporation liable for such damages, and against any person who received payment for such damages, which action shall be commenced and tried in the county in which such lien shall be filed, unless ordered removed to another county by the court for cause. If the claimant shall prevail in such action, the court may allow reasonable attorneys' fees and disbursements. Such action shall be commenced within two years after the filing of such lien.