Patent It Yourself - PDF Archive

248 | Patent it YOURSELF
18. A rifle having an upwardly curved barrel.
19. The rifle of Claim 18 wherein said barrel is made of
austenitic steel.
The dependent claim (19) will be treated independently,
but with Claim 18 incorporated, so that it effectively reads
as follows:
19. A rifle having an upwardly curved barrel, said barrel
being made of austenitic steel.
Tip
Use Only Significant Limitations. You can make
your dependent claims as specific as you want, even to
reciting the dimensions of the tabletop, its color, etc. However,
extremely specific limitations like this, while possibly defining
an invention that is novel over the prior art (Section 102), do
not recite unobvious subject matter (Section 103), so they’ll be
of little use to fall back on if you lose your independent claim.
Thus, you should mainly try to use significant limitations in
your dependent claims—that is, limitations that an infringer
might use if he or she made your invention.
You should draft dependent claims to cover all possible
permutations of the subsidiary features of your invention.
For example, suppose you’ve invented a telephone and some
of the dependent features are that it has (a) a musical ringer,
(b) a coiled cord, and (c) a stand. You can provide three
dependent claims with features a, b, and c, respectively.
Then write four more dependent claims with features a
and b, a and c, b and c, and a, b, and c, if you think these
combinations are feasible.
Although most of your dependent claims should have just
a single element (to obtain maximum claim differentiation),
you should try to draft at least one dependent claim with as
many parts as possible so as to provide as broad a base as
possible for maximizing infringement damages. Also try,
insofar as possible, to draft at least one claim to cover parts of
the invention whose infringement would be publicly verifiable,
rather than a nonverifiable factory process or machine.
As with independent claims, you should not make
your dependent claims purely “functional”—that is, each
dependent claim should contain enough physical structure
to support its operational or functional language. Here are
some examples.
Wrong:
17. The bicycle of Claim 16 wherein said derailleur
operates with continuously variable speed-to-power
ratios. [This claim has no structure to support its
operational limitation.]
Right:
17. The bicycle of Claim 16 wherein said derailleur
contains means for causing it to operate with
continuously variable speed-to-power ratios. [The
“means” limitation is a recitation of structure that
supports the operational limitation.]
Right:
17. The bicycle of Claim 16 wherein said derailleur
contains a cone-shaped pulley and a belt pusher for
causing it to operate with continuously variable speedto-power
ratios. [The pulley and pusher constitute
structure that supports the operational limitation.]
If your independent claim recites a means plus a
function, your dependent claim should modify the means
and not the function. For example, assume an independent
Claim 20 recites, “variable means for causing said
transmission to have a continuously variable gear ratio.”
Here are the right and wrong ways to further limit this
“means” in a dependent claim.
Wrong:
21. The transmission of Claim 20 wherein said
continuously variable gear ratio ranges from 5 to 10.
Right:
21. The transmission of Claim 20 wherein said variable
means is arranged to provide ratios from 5 to 10.
Common Misconception: If a dependent claim recites a
specific feature of your invention, say a two-inch nylon gear,
your invention will be limited to this gear, so that if any
copy of the invention uses a one-inch gear, or a steel gear, it
won’t infringe on your patent.
Fact: Although the copy won’t infringe the dependent
claim, it will infringe the independent claim so long as it
isn’t limited to this specific feature. And as long as even one
claim of a patent is infringed, the patent is infringed and
you can recover as much damages (money) as if 50 claims
were infringed.
Common Misconception: If a dependent claim recites a
feature or element of the invention, it will protect this
feature per se.
Fact: A dependent claim must be read to include all of the
features of its referent claim (preceding or independent
claim to which it refers). Thus it will not cover the feature
it recites per se, but rather will cover that feature in
combination with all of the elements of its referent claim.