The appeal board of the workmen’s compensation department affirmed an award of benefits to plaintiff in March of 1959. In July of the same year, she filed an application for hearing and adjustment of claim for interest upon all benefits awarded *142to her paid after their due dates. Our decision in Wilson v. Doehler-Jarvis, 358 Mich 510, by which we first determined that such interest is recoverable, was made in the following January of 1960, and in the opinion announcing that decision a majority of this Court said, at p 517, “This decision shall not, however, be regarded as retroactive.” One month after our decision in Wilson v. Doehler-Jarvis, a workmen’s compensation department referee passed upon plaintiff’s application and claim pending at the time of our decision in Wilson and awarded plaintiff the interest she claimed. The award was subsequently affirmed by the appeal board and we granted leave to defendants to file this appeal.
Defendants contend that plaintiff should not have been awarded interest on an award after it was made and after the appeal period had expired. It is their claim that the original award was res judicata of all claims that could have been made in the original proceedings whether or not they were in fact presented and considered.
We have previously held, in Besonen v. Campbell, 243 Mich 209; Valisano v. Chicago & Northwestern R. Co., 247 Mich 301; and in eases cited in the dissenting opinion in Hayward v. Kalamazoo Stove Co., 290 Mich 610, at p 649, that the doctrine of res judicata applies to workmen’s compensation claims before the department. Defendants objected, for this reason, to the proceedings before the referee and the appeal board for the determination of plaintiff’s interest claim. Their objection was valid and should have barred further proceedings after expiration of the period for appeal from affirmance of the award in March of 1959 by the appeal board. Accordingly, it cannot be said that the award of interest in plaintiff’s favor 1 month after our decision in Wilson v. *143Doehler-Jarvis, supra, was made in a case then pending before the department.
Reversed. No costs.
Black, Kavanagh, Otis M. Smith, and Adams, JJ., concurred with Souris, J.
Carr, C. J., and Dethmers and Kelly, JJ., concurred in result.