Professional liability insurance—sometimes called malpractice insurance or errors and omissions insurance—is insurance that may be purchased by attorneys and law firms to pay the costs of defending legal malpractice claims, and the costs of settling such claims or paying the judgment awarded to a plaintiff on such a claim. Most states do not require attorneys to purchase professional liability insurance, but some states require attorneys who do not carry professional liability insurance to provide notice to their clients of that fact. Some states require attorneys to have their clients sign a written disclosure that the attorney does not have professional liability insurance.

In the state of Oklahoma, attorneys are not mandated by state law to carry professional liability insurance, commonly known as malpractice insurance or errors and omissions insurance. However, the Oklahoma Rules of Professional Conduct, specifically Rule 1.4, require attorneys to communicate effectively with their clients, which may include informing them about the attorney's insurance status if it is relevant to the client's decision to employ the attorney. While there is no explicit statutory requirement for attorneys to notify clients if they lack professional liability insurance or to have clients sign a written disclosure to that effect, it is considered good practice for attorneys to be transparent about their insurance status. Clients may consider an attorney's insurance coverage as a factor in their hiring decision, and attorneys may voluntarily choose to inform clients of their insurance status to maintain trust and transparency.