Hearts have been found guilty of breaching Scottish Premier League rules over a failure to pay bonuses and appearance monies.
A meeting was held at Hampden on Monday to consider two charges relating to the Premier League club's payment of bonuses.
A statement from the SPL read: "The sub-committee found the club guilty of breaching SPL Rules A6.21 and A6.22 in respect of a number of players. The club remains subject to the existing registration embargo, which will continue in effect until such time as the SPL board is satisfied that the remuneration default is no longer ongoing.
"However, the decision of the sub-committee today was that the club should be made subject to further restrictions on the registration of players.''
The restrictions relate to how and when Hearts can sign players. Despite winning the Scottish Cup in May with a 5-1 win over Edinburgh rivals Hibs, Hearts have endured a torrid 2012 off the field.
A £450,000 winding-up order was recently averted, while an agreement was reached over a separate issue to pay £1.5 million over a three-year period. Hearts raised £1m from a share issue designed to raise £1.79m and face a shortfall of £800,000 this season unless attendances are above expectations.
Manager John McGlynn was installed in the summer, tasked to introduce young players, and recognises the challenge Hearts face to reduce costs. Their leading players could depart during the winter transfer window, forcing McGlynn to select inexperienced players.
Speaking last week, McGlynn said: "We're going to have to go through a transitional period right now and another one in the summer. That's how it will be.
"If we have to put more younger players into the team then fair enough. That was my brief, to come here and try to bring through young players. This is probably the most difficult time for Heart of Midlothian Football Club. I don't think they've ever had a transfer embargo in the past or been so close to a winding-up order. It's a big challenge.''
Information from the Press Association was used in this report