Where can an infringement action be filed?
Section 1400(b) permits suit where the defendant resides, or where it has committed acts of infringement and has a regular and established place of business. TC Heartland v. Kraft Foods holds that a domestic corporation resides in its state of incorporation for this purpose. Applying the statute to a particular district and defendant requires specific facts; nationwide sales alone do not supply the statute's complete test.
How is convenience transfer different?
Section 1404(a) permits transfer for the convenience of parties and witnesses and in the interest of justice, subject to its destination requirements. A case can satisfy the venue statute and still raise a transfer question. Identify witnesses, records, relevant operations, and the proposed destination rather than treating venue and convenience as the same issue.
When should I raise the objection?
Review it before the first response. Rules 12(g) and 12(h) impose consolidation and waiver rules for personal-jurisdiction and improper-venue defenses. Foreign defendants require separate analysis, including 28 U.S.C. 1391(c)(3); the domestic-corporation holding should not be applied to them without that analysis.