The US Department of Justice (DoJ) has concluded an investigation into Samsung’s use of a special class of essential patent portfolio to hit its competitors, while would keep an eye on related patent proceedings.

DoJ added that the South Korean firm will not be penalised for its efforts to ban the sale of some of the Apple products from the US market.

DoJ said in a statement that there is a threat that the patent holder could use the threat of an exclusion order to obtain licensing terms that are more onerous than would be justified by the value of the technology itself.

"The U.S. Trade Representative (USTR) reviewed the exclusion order issued by the ITC against Apple at Samsung’s request and overturned it, determining that it was not consistent with the public interest," DoJ added.

"As a result of the USTR’s action, the Antitrust Division has determined that no further action is required at this time.

"The Antitrust Division is therefore closing its investigation into Samsung’s conduct, but will continue to monitor further developments in this area."

Apple was sued by Samsung at the US International Trade Commission (ITC) and won an order in June 2013 to ban the sale some older iPhone and iPad versions in the US.

Last week, both the smartphone makers have submitted their final list of infringed patents for their next trial, with both accusing the other of breaching their patented technologies.