Key facts: Standing to contest requires being an interested party such as a beneficiary or heir-at-law; Valid grounds include lack of testamentary capacity, undue influence, fraud, duress, and improper execution; Objections must be filed within statutory timeframes before probate is finalized; The $50,000 estate value limit may determine simplified probate procedures that affect contest timing; A 30-day waiting period applies before objections can be filed in many probate proceedings; Oregon circuit courts have exclusive jurisdiction over will contests.