In the unusual case where an opposition is limited to only a certain part of the patent, the opposition division has to limit its examination to the part opposed. However, if the opposition is directed only to an independent claim, the dependent claims are considered to be implicitly covered by the extent of the opposition and may be examined by the opposition division, provided their validity is prima facie in doubt on the basis of the information already available (see G 9/91). Similarly, if only a process claim is opposed, a product-by-process claim making reference to the same process is considered to be implicitly covered by the extent of opposition and may be examined under the same conditions as above (see T 525/96).