Learning Tree International’s top executive and his wife have submitted an offer to take the company private in a deal that would lift the professional development firm’s value to $69.2 million.

Chief executive David C. Collins and Mary C. Collins currently own nearly a third of the company’s shares and have proposed purchasing the remaining ones for $5.25 each, roughly 20 percent higher than its recent trading price.

Based in Reston and founded in 1974, Learning Tree provides software and instructor-led training courses for information-technology and business professionals around the world. Collins was appointed CEO back in January.

“We believe that now is an opportune time for the Company to consider this proposal,” the Collinses wrote in their offer letter to the Board of Directors. “Both the Company’s recent and previous attempts to enhance stockholder value through such measures as improvements to existing businesses, managing costs, increasing the sizes of the direct sales force and the course library, and share repurchases, have had little impact on the Company’s stock price.”

The couple argued that they are “uniquely positioned” to negotiate a deal taking the firm private given their familiarity with its operations. Should the offer be approved quickly, the Collinses intend to close the deal by the end of the year, which would allow shareholders to take advantage of low capital gains tax rates that are scheduled to expire at the end of 2012.

Soon after, the couple announced its offer, national securities law firm Tripp Levy said it is investigating whether Collins and his fellow board members are sidestepping the law by electing not to conduct a full auction for the company. Attorneys will be looking into whether investors would receive the highest price possible for their shares, which have traded as high as $9 in the past year.

Learning Tree’s board of directors has formed an independent committee to evaluate and consider the proposal but provided no anticipated timeline for a decision. However, that shares have yet to hit $5.25 in the week following the announcement suggests investors have at least some doubt the deal will be approved.