Build two files: the crash claim and the coverage claim

Collect policies for the claimant, household members, occupied vehicle, owner, employer, and any other potentially relevant source. Obtain declarations, endorsements, applications, renewals, selection or rejection forms, vehicle schedules, named-driver terms, household definitions, occupancy provisions, territorial terms, limits, anti-stacking language, priority or other-insurance clauses, medical-payments coverage, and exclusions. Identify whether the claimant was a named insured, resident relative, occupant, permissive user, employee, pedestrian, cyclist, or another defined person.

Confirm the adverse vehicle's liability coverage, limits, denial, insolvency, unknown status, or insufficiency. An underinsured analysis requires a supported damages picture and the legally relevant available liability limits. It is not established merely because those limits are lower than a demand. A hit-and-run or phantom-vehicle matter may present notice, corroboration, physical-contact, reporting, and proof questions under the policy and current law. Do not state a universal rule without the issued form and event facts.

The crash file should preserve scene photographs, vehicles, event data where available, police and dispatch records, witness information, video, road and weather conditions, citations without treating them as dispositive, repair records, and reconstruction material when warranted. The injury file should establish symptoms, treatment, diagnosis, prior and later conditions, medical cause, prognosis, bills, income, care needs, and other legally supported losses. The coverage file should establish policy status, claimant status, vehicle use, premiums, selection or rejection, and all notices.

Build a communication chronology for both insurers. Preserve liability tenders, coverage letters, limits information, settlement proposals, releases, consent requests, subrogation communications, proof submissions, recorded statements, examinations, medical authorizations, evaluations, offers, and payment accounting. The UM/UIM carrier's claim file may raise privilege, work product, privacy, and discovery questions, particularly after positions become adversarial. Keep native records and let counsel choose the lawful process for internal material.

Before settling with or releasing the adverse driver, identify every potentially applicable UM/UIM policy. Read notice, consent, subrogation, exhaustion, settlement, trust, and reimbursement terms. Determine what the carrier needs to evaluate the proposed resolution and what current Oklahoma law requires. Do not assume consent, substitute-payment, waiver, or subrogation consequences from another state's rule or an older policy form. Preserve the proposed release and all communications before execution.

Evaluate insured status and event; adverse legal responsibility; damages; available liability coverage; policy limits and priority; offsets; conditions; and handling. A genuine medical-cause or value disagreement does not eliminate review of the carrier's investigation and response to material proof. Oklahoma Insurance Department guidance provides consumer context; the statute, issued policy, selection history, and current appellate treatment control.

Build damages from admissible proof. List liability and UM/UIM limits, medical-payments benefits, workers' compensation, health and disability benefits, liens, subrogation claims, settlements, write-offs, and prior payments separately. Apply each under the policy and law—not mechanically. Stacking, priority, offsets, setoffs, credits, exhaustion, and reimbursement require provision-specific review.

Calendar crash, discovery, policy notice, adverse claim, treatment, coverage and selection-record requests, limits disclosure, tender, proposed settlement, consent, release, UM/UIM submission, examination, decision, payment, suit, and preservation. For an unknown vehicle, add prompt reporting plus witness, video, vehicle-data, and road-camera retention. Carrier negotiation may not toll a contract or tort period. Minor, estate, guardianship, bankruptcy, workers' compensation, public-entity, or Tribal issues may add procedures.