Microsoft Corp v Motorola Mobility LLC

Patent claims are construed purposively in context, but deliberate claim limitations must be given effect. Terms such as “transceiver”, “message” and “status” may bear different meanings in different claim contexts. “Responsive to” does not require the relevant event to be the sole or immediate cause of a later transmission.

For novelty, prior art must disclose subject matter which would necessarily infringe and must disclose it sufficiently to enable performance. Obviousness is assessed using the structured inquiry into the skilled person, common general knowledge, the inventive concept, differences from the prior art and whether those differences require invention. A patent may be invalid even though infringement would otherwise be established.

Motorola alleged that Microsoft infringed European Patent (UK) No. 0 847 654, concerning synchronisation of message or device status across multiple communication devices. Microsoft denied infringement and counterclaimed for revocation on grounds of lack of novelty and obviousness.

The proceedings concerned construction of the claims, three items of prior art, common general knowledge in paging and email systems, alleged infringement by Exchange ActiveSync and Live Messenger, and the effect of a cross-licence between Microsoft and Google. The central issues were whether the claims were valid and, if so, whether Microsoft’s products infringed them.

1. Construction. “Transceiver” was not confined to a pager. The Patent expressly contemplated other two-way communication systems, and claim 7 was not limited to wireless systems. In claim 1, the first message contained user-relevant information, while the second and third messages were control messages concerning that information. “Status” referred to the condition of a message in claim 1, but to the condition, operating mode or information content of a transceiver in claim 3.

2. “Responsive to” did not require the receipt of the second message to be the sole cause of transmission of the third message, nor did it require immediate transmission. The construction included a system in which other causes, potentially including an update request from another transceiver, operated concurrently. The construction adopted was therefore the one advanced by Microsoft.

3. Novelty. Gutman anticipated claims 3, 5 and 7, subject to the construction of “in response to” in claim 7. Gutman did not clearly disclose the synchronisation of message statuses required by claim 1. PCMAIL and IMAP4 anticipated claim 7. The novelty inquiry required prior art both to disclose subject matter which would necessarily infringe and to enable the skilled person to perform it.

4. Obviousness. Claims 1, 3–5 and 7 were obvious over common general knowledge in paging, including the hospital-group messaging scenario. Claims 1, 2 and 6 were obvious over Gutman. Claims 1–6 were obvious over PCMAIL and IMAP4. The differences involving wireless implementation and, on Motorola’s construction, infrastructure-initiated updates, did not require invention.

5. Infringement and licence. If valid, claims 1, 3, 5 and 7 would have been infringed by supplying means essential for implementing EAS and Live Messenger, under section 60(2) of the Patents Act 1977. The EAS implementations actually described involved client requests and therefore did not infringe even on Motorola’s construction. In any event, Microsoft could rely on the Google Licence in relation to EAS.