According to Newsforge, HP in the US has confirmed the memo's legitimacy. A spokeswoman for HP in the UK was not immediately able to comment.
The memo goes on to say that HP would seek ways to "reduce our exposure" to open source and "lower our profile" while still shipping products. Although HP was covered by cross-licensing deals up to 2001, the memo said, patents filed after June 2001 that year would not be included.
"Microsoft could attack open-source software for patent infringements against OEMs, Linux distributors, and least likely open-source developers. They are specifically upset about Samba, Apache and Sendmail. We believe Samba is first, and they will attempt to prove it isn't covered by prior patent cross as a so called "clone" product carve out in the previous agreement," the memo said. "OEMs that don't have a cross (like SUN), or OEMs like HP that they force a change in their cross licence to exclude open-source software are probably the first target. Intel, Red Hat, SuSE, UBL, Oracle are probably in the first wave as well."
Microsoft embarked on a campaign last year to increase its revenue from patents and enlarge its intellectual property portfolio. It has received patents on a wide variety of apparently elemental computing components such as to-do lists, double clicking and storing documents in XML format, and had another 5000 applications in the pipeline as of November 2003. Last year, Microsoft also hired IP guru Marshall Phelps -- previously architect of IBM's $2bn-a-year IP strategy. He is on record as saying that Microsoft intends to spend $7bn annually on IP issues.
The company has recently said that it would make most or all of its portfolio available for licensing on "commercially reasonable" terms, a key phrase that makes it easier to uphold patent cases in court. It has also been settling many outstanding cases out of court, and is in the final stages of its European antitrust battle.