4.3.8 Reasons for a decision allegedly surprising
"Grounds or evidence" under Art. 113(1) EPC is understood as the essential legal and factual reasoning on which a decision is based (see chapter III.B.2.3.2 "The meaning of 'grounds or evidence'").
While the boards are not obliged to provide the parties in advance with all reasons for a decision in detail (see in this chapter V.B.4.3.5), Art. 113(1) EPC requires that decisions may only be based on grounds or evidence on which the parties concerned have had an opportunity to present their comments. In R 3/13 the Enlarged Board held that this implied that a party may not be taken by surprise by the reasons of a decision referring to unknown grounds or evidence (see also R 15/09, R 21/10).
In R 3/10, R 15/11 and R 16/13 the petition was allowed because of surprising reasons on which the parties had not been given an opportunity to comment (see in this chapter V.B.4.3.19). On the other hand, in R 19/11 the Enlarged Board held that there can be no denial of the right to be heard if a board of appeal, after hearing all parties in inter partes proceedings, subsequently reaches its own conclusion which is then recorded in its written decision (see also R 15/12, R 16/13, R 10/17, R 7/18).
In R 6/18 the Enlarged Board found that it could not come as a surprise that the board, when deciding whether there was an unambiguous disclosure of the claimed invention, did not only consider the passage sensu stricto referred to by the petitioner but also the sentences which directly followed that passage. Parties had to be aware that in general the question of added matter could not be decided by simply relying on isolated passages of the description but required a comprehensive analysis of the application documents.
Referring to R 8/13 of 15 September 2015 date: 2015-09-15, the Enlarged Board stated in R 5/19 that submissions parties made (only) in writing also had to be taken into account and that appeal proceedings were conducted mainly in writing. Parties were not required to reiterate those written submissions at the oral proceedings to ensure they were taken into account in the decision.