It is well known that the EPO is quite strict when assessing whether amended claims contain “new matter” (A 123). It is not always well understood that the very same approach applies when it comes to the validity of the priority claim. As a matter of fact, the case law uses the same criterion (“directly and unambiguously”) for amendments (A 123), divisional applications (A 76), novelty (A 54) and priority (A 87). It’s really all of one piece.
The present appeal was filed after the Opposition had revoked the patent under consideration for lack of novelty over some A 54(3) prior art. Unsurprisingly, the validity of the priority claim was discussed in the appeal proceedings.
Claim 1 of the main request before the Board read:
Process for the epoxidation of olefins byi) reacting an olefin with hydrogen peroxide in the presence of an epoxidation catalyst and an alcoholic solvent, whereby hydrogen peroxide is employed as an aqueous solution containing 10 to 70 wt.-% of hydrogen peroxide or as an alcoholic solution prepared by reaction of hydrogen and oxygen in the presence of a noble metal catalyst and the alcohol;ii) separating product olefin oxide and unreacted olefin from the reaction product of step i);iii) recovering a stream comprising the alcoholic solvent,characterized byiv) subjecting the recovered stream of step iii) to hydrogenation,whereby the olefin is propene and propene is used mixed with propane.
The Board found the priority claim to be invalid, for the following reasons:
[2.1] Claim 1 of the main request relates to a process for the epoxidation of olefins comprising steps i) to iv). In step i), an olefin is reacted with hydrogen peroxide in the presence of an epoxidation catalyst and an alcoholic solvent, and, in step ii), olefin oxide and unreacted olefin are separated from the reaction product of step i). According to the feature introduced at the end of claim 1, “the olefin is propene and propene is used mixed with propane” […].
The standard to be applied in deciding whether the claimed priority date is to be acknowledged is whether this subject-matter is directly and unambiguously derivable from the priority document D28 as a whole (see decision G 2/98 [headnote]).
In the claims of priority document D28, the term “propane” only appears in claim 13.
However, in this claim, specific percentages by weight of this component are defined for the product stream and the overhead product obtained from steps i) and ii), respectively. Moreover, claim 13 is dependent on claim 12, which relates to a specific epoxidation reaction wherein “the catalyst is a titanium silicalite and the solvent is methanol”. Hence, this very specific disclosure cannot provide a basis for the much more general subject-matter claimed in claim 1 of the main request.
As regards the content of the description of priority document D28, it is disclosed on page 6, lines 7 to 11, that propene is the preferred olefin to be used in the epoxidation reaction. Further down on the same page, it is specified that “propene may be used mixed with propane in an amount of between 0 and 10 vol.% of propane” (page 6, lines 28, 29; emphasis added). Thus, the propene feed is defined as optionally containing propane, but only in a maximum amount of 10 percent by volume. This passage cannot therefore provide a direct and unambiguous basis for the use mixtures of propene and propane without any limitation as to the relative amounts thereof.
The appellants referred to page 12, lines 11 to 18, and page 16, lines 20 to 24, as providing a basis for a general disclosure of the use of propene mixed with propane in the reaction of step i), without limitation on the amount of propane.
The cited passage on page 12 is embedded in a section starting on page 11, line 4 and ending on page 12, line 24, relating to “one embodiment of the present invention” in which “the reaction mixture is separated in a pre-evaporator into an overhead product containing propene, possibly propane, propene oxide and solvent, and into a bottom product ...” (page 11, lines 4 to 7). Thus, this embodiment illustrates specific means for working up the reaction product of step i), and cannot therefore provide a basis for introducing a definition as to the composition of the olefin to be used in the general context of the epoxidation reaction. Indeed, as an “embodiment of the present invention”, the cited passage must be read in the context of the previous section of the description relating to the epoxidation step i) (see page 6, line 7 to page 8, line 9). Here, the amount of propane that may be present in the propene feed is clearly restricted to 10 volume, as explained in the previous paragraph.
Similarly, the cited passage on page 16, lines 20 to 24, is embedded in the section of document D28 relating to specific examples (see page 15, line 16 to page 18, line 16). On page 16, line 4, there is a reference to “a propene feed”, but it is not specified that this contains propane. However, the overhead product, separated in the pre-evaporation stage, contains propane (page 16, lines 15 to 17), and an uncondensed portion of this stream containing propane is returned to the epoxidation reaction (page 16, lines 22 to 24). It can therefore be concluded that the propene feed used in the examples must contain some propane, but it is not specified how much. This is not equivalent to a direct and unambiguous disclosure that unlimited amounts of propane may be present in the propene feed, particularly not in the context of a more general disclosure as now claimed.
For these reasons, the board concludes that the subject-matter of claim 1 of the main request is not entitled to the priority date of 2 May 2002, but only to the filing date of 29 April 2003 […].
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