Claim Construction, Clarity, Support and Amendment Practice
Construction
Under Malaysian law the scope of protection is determined by the claims, with the description and drawings used to interpret them. Malaysian courts have adopted a purposive approach: identify the inventive concept and ask what a skilled reader would understand the claim to mean, not merely the literal meaning. Extrinsic evidence is secondary; the specification is the primary dictionary.
Clarity and support
Claims must be clear and supported by the description. Clarity issues include ambiguous terms such as "about" or "substantially", inconsistent claim sets, and unclear antecedents. Support requires that the claimed subject matter be derivable from the description without undue burden. Functional claims must be matched by adequate disclosure.
Amendment
Amendments to pending applications and granted patents are permitted but must not add matter and, after grant, must not broaden the claim. Amendments are examined for compliance; third parties may oppose. In infringement or revocation proceedings, the court may allow amendment.
Worked example
Claim: "A container substantially as described herein." This is unclear and lacks support because it incorporates the description by reference. Amend to recite the specific structural features, for example "a cylindrical body with a threaded neck and a complementary cap". The amendment is allowable if those features are in the original disclosure; it narrows the claim, so no broadening issue arises.
Traps
- Reading the claim literally and ignoring the description.
- Using prosecution history to narrow scope without a clear basis.
- Amending to add a feature not originally disclosed.
- Broadening a granted claim.