The Oklahoma Bar Journal January 2026

1) Whether the increase

Regarding whether the business, as a whole, belonged to the husband as his separate property, the court upheld the trial court’s decision, noting several key facts: 1) The business was formed more than two years before the couple married. 2) The couple broke up for almost a year between busi ness formation and marriage. 3) The wife testified that her role in the business was “minimal” prior to the marriage. 4) The tax records listed the husband as the sole owner of the business for tax purposes. 13 However, regarding increased business profits, the court did not uphold the trial court’s decision that business growth was the hus band’s separate property and not subject to equitable division. 14 The court observed that the following factors should be con sidered when deciding whether the increased profits should be classified as marital property:

and the context of the overall business operations. 7 An added layer of complexity arises when an asset was owned by one spouse before marriage, but the asset’s value increased during mar riage. This scenario was addressed by the Oklahoma Supreme Court in the foundational case of Thienlenhaus v. Thienlenhaus . 8 In that case, the court articulated that an increase in value of one spouse’s separate property that is attributable to either spouse’s efforts, contribu tions or skills is calculated into the marital estate. 9 But if the increase was due to market forces, then it remains the separate property of one spouse. 10 However, it is import ant to note that in Thienlenhaus , the asset in dispute was a passive retire ment account, which is compara tively less complex to value than a privately owned business. 11 In the recent case of Williams v. Williams , the Oklahoma Court of Appeals applied the Thienlenhaus test to determine whether the trial court erred in finding that the par ties’ limited liability company (LLC) and its increased profits were the separate property of the husband. 12

occurred during marriage 2) If the increase was a result of passive (market forces) or active income (marital efforts) 3) Proof of the increase, usu ally by expert testimony and adequate financial records 4) Whether there is a causal link between marital efforts and an increase in profits In applying these factors, the court observed that the evidence showed that during the marriage, the husband exerted tremendous efforts directly related to the operation and growth of the busi ness. 15 The husband was the sole owner, executive and exclusively controlled the day-to-day business operations. 16 The husband made and received thousands of phone calls each month in connection with the business, but the court found that the wife also exerted efforts, even though those efforts were “not relevant to [the] hus band’s efforts.” 17 Thus, Oklahoma case law suggests that it is fairly easy to meet the burden of showing that the increased profits of a busi ness in dispute were due to joint industry and, therefore, subject to equitable division. However, this determination is only one part of a multilayered analysis. valuation date is not fixed by stat ute. Instead, the date is left to the discretion of the trial court. 18 This judicial flexibility allows the court to select a date it deems reasonably just under the circumstances. 19 The court will often choose between the date of separation, the date of trial or the date the decree of THE VALUATION DATE In Oklahoma, a business’s

Statements or opinions expressed in the Oklahoma Bar Journal are those of the authors and do not necessarily reflect those of the Oklahoma Bar Association, its officers, Board of Governors, Board of Editors or staff.

26 | JANUARY 2026

THE OKLAHOMA BAR JOURNAL