(after stating the facts as above). [1] In addition to the mechanical concept above set forth, the patentee had a secondary idea described in the specification and covered by claims not in suit. If the spring handles are moved on their journaled ends, with nothing but friction retarding motion, they may become loose like the bail of a bucket similarly journaled (see Weber, 550, 429).
To prevent this, Baltzley so inclined the edges of his tubular rolls touching the spring handles as to produce a camming effect, which (cammed surface co-operating with spring handle) produced a snap action, forcing said spring handle into the final forward or backward position, as might be desired. This subsidiary advantage does not affect this case, which, as its first query, asks whether the invention, without the camming adjunct, presents patentable novelty. -
The patent of Dudley (622,610) is the nearest and best reference. It shows a clip of bent resilient metal, elliptical in cross-section, and distended by applying to each clip edge a tool of metal, which by a “tongue and groove” arrangement seizes an edge, and when laid back, like Baltz-ley’s handles, furnishes the necessary leverage. These tools were removable, and were to be used for any number of clips; yet, if the user desired, 1hey might be turned forward, much like Baltzley’s handles, and left flat against the papers in the clip.
The merest examination of this device shows it to be cumbersome, expensive, and difficult, if not dangerous, in operation. Yet it was a machine of sorts, and when it functioned at all it did so for the same mechanical reason as does that of the patent in suit. This patentee’s contribution to the art, consisted in devising a new, simple, and convenient method, not strictly of operation or function, hut of co-operation. There could hardly be a better example of the truth of the remark of Lacombe, J., in Miehle, etc., Co. v. Whitlock, etc., Co., 223 Fed. 650, 139 C. C. A. 204:
“Patentable novelty is sometimes found in discovering wliat is tbe difficulty with an existing structure and what change in its elements will correct the difficulty even though the means for introducing that element into the combination are old and their adaptation to the new purpose involves no patentable novelty.”
*426So here, whatever Baltzley’s intellectual processes really were, he might well have considered Dudley, and by substituting for Dudley’s clumsy and separate tools a spring wire handle, journaled externally to the clip sides, produced (as he did) an admittedly inexpensive, useful, and salable article, simply by correcting the “difficulty with the existing structure”; i. e., Dudley’s, which never had (on this record) any field of practical utility. We have no doubt that patentable invention is disclosed by the foregoing.
There being no difference, mechanical or structural, between defendants’ article and that of the claims in suit, other than the positioning of the steel spring handles, infringement would seem plain. Here the trial court fell into error in considering the subsidiary camming adjunct as Baltzley’s single contribution to the art. This is a mistake. The invention advanced in this suit was made without any reference to a cam.
[2] The argument for noninfringement is sought to be strengthened by reference to the Contents of the file wrapper. On this point our view was restated in Spalding v. Wanamaker, 256 Fed. 533, — C. C. A. —, viz. that the only purpose for which the file wrapper can be examined is to ascertain whether estoppel has arisen through rejected claims. See, also, Walker on Patents (5th Ed.) § 187a. The reason why that may be important is because the doctrine of estoppel holds “the utterer to the truth of his speech.” Babbitt v. Read, 236 Fed. 45, 149 C. C. A. 252.
Having from this viewpoint examined the file wrapper, we are of opinion that the patentee’s disclosure stated fully and at first facts sufficient upon which to ground the claims in suit, and such claims or their equivalents he never receded from. Many claims, first propounded, were obviously too broad; but Baltzley never “accepted limitations imposed by the rejection of broader claims” and affecting the claims in suit. The residuum is ample for the purposes of this case. See Goodwin, etc. Co. v. Eastman, etc., Co. (D. C.) 207 Fed. 357, affirmed 213 Fed. 231, 129 C. C. A. 575.
This camming effect, however, must be considered from another angle. The device of defendants’ patent further attempts to differ in its mechanics from that of the patent in suit, in that its cam is transferred from the edge of the tubular jaw to the spring handle; but the triviality of any cam is proven by the style of defendants’ commercial article shown as an exhibit in this court, which works well, does everything indicated by the claims in suit, and has no cam at all. Friction, is enough for practical purposes.
[3] Finally, it is urged that plaintiffs’ laches should forbid the remedy of accounting. On this subj ect there is no evidence; but a comparison of dates shows that defendants (who were infringing before Baltzley’s patent issued) were not sued until something less than three years after such issuance. It is not profitable to mention decisions wherein this or that lapse of time has been held sufficient to justify this defense; for “laches is not a mere matter of time, like limitation, but is a question of the inequity of enforcing the claim.” Hubbard v. Manhattan Trust Co., 87 Fed. 59, 30 C. C. A. 528 and cases cited. It is *427now argued that defendants exercised great care to avoid infringing, and should therefore have been promptly sued for their own advisement. We think that, in the sense of careful studying under professional advice, and after personal warning from plaintiffs, just how near to plain copying their intended imitation might go, they were very careful. Their patent shows it; and we are quite unable to see how, if Baltzley had issued when Spengler was considered by the Office,1 Spengler could have failed of rejection “on Baltzley of record.” _
_ Under such circumstances, there is no inequity in regarding this infringement as persistence in wrongdoing, when the light was unusually strong.
'Decree reversed, with costs, and case remanded, with directions to grant plaintiffs the relief prayed for in their bill.