This is an appeal from a decision of the Board of Patent Interferences awarding priority of invention in Interference No. 91,815 to Oliver, the senior party.1 The two counts in issue originated as claims in a patent2 to Mc-Cutchen, Jr., and Eskilson, the junior party, hereafter McCutchen.
Both parties took testimony in attempting to establish priority. The board, upon consideration of the evidence, held that Oliver had reduced to practice “as early as the end of May 1955” and McCutchen was “accorded July 28, 1955 for reduction to practice.” The board also held that “Oliver is entitled to make the claims corresponding to the counts.” Appellant argues here that first, Oliver’s disclosure does not support the counts and second, Oliver’s evidence does not establish a reduction to practice at the end of May 1955. Our disposition of this appeal requires only a consideration of Oliver’s disclosure. In this respect we agree with appellant’s arguments and the decision of the board therefore must be reversed.
The test to be applied where it is alleged that a disclosure does not support a claim for interference purposes is that which was recently applied in Henderson v. Grable, 339 F.2d 465, 52 CCPA 920. There Judge Martin, speaking for an unanimous court, reaffirmed this court’s position, stating as follows:
* * * As Judge Rich stated for this court in Hall v. Taylor, 332 F.2d 844, 51 CCPA 1420, 1424:
We find in the Dreager [In re Draeger et ah, 150 F.2d 572, 32 CCPA 1217], opinion what we consider the key to determining whether a disclosure supports a claim for interference purposes * * * viz., does the disclosure teach the gist of the invention defined by the claim?
See also Swain et al. v. Crittendon, 332 F.2d 820, 51 CCPA 1459.
The “gist of the invention” test referred to in the Henderson case is a sound principle of interference law and is the key to determining whether the counts here in issue are supported by the Oliver disclosure. As this court stated in Henderson, supra, 339 F.2d at 470:
Appellee and the board cite numerous cases in support of classic propositions of interference law, such as, clearly expressed limitations may not be disregarded, all recitations are material, equivalency of function may not be considered, and so on. We do not disagree, but a study of those cases shows that they are not apposite to the facts here. * * *
“The gist of the invention,” states probably more clearly than other propositions of interference law, that the purpose of an interference is to determine “priority of invention,” 35 U.S.C. § 135, 35 U.S.C. § 102(g). There is no right to an interference under the patent laws unless the counts are supported by the specification of the applicant who copies a claim from another’s patent. This requires at a minimum that such specification disclose the mutually claimed invention. Unless it does, the inquiry as to priority should come to an end.
THE INVENTION(S)
The counts in issue are as follows:
1. A magnetic transducer head unit comprising a magnetic head having opposite pole pieces presenting confronting lapped pole tips on opposite sides of a recording/reprodueing gap, and a bracket supporting said head and presenting at either end of the head broad reference surfaces lapped co-planar with the pole tip of one of said pole pieces.
2. A multichannel magnetic transducer head unit comprising a series of individual magnetic heads, each of said individual heads comprising opposite pole pieces presenting con*611fronting lapped pole tips on opposite sides of a recording/reproducing gap, and a bracket supporting said individual heads in side-by-side relation with their respective lapped pole tips eoplanar and their recording/reproducing gaps aligned, said bracket presenting at either end of the series of heads broad reference surfaces lapped eoplanar with the pole tips at one side of the aligned recording/reproducing gaps.
The statutory requirement of section 112 is that the claims shall particularly point out and distinctly claim “the subject matter which the applicant regards as his invention.” Here the claims of the McCutchen patent which were copied by Oliver to become the counts of the present interence are so worded that reference to the specifications of the respective parties becomes necessary to ascertain the meaning of certain language therein. One cannot arrive at an understanding of the present counts as they relate to the subject matter of the interference without something more than the counts themselves.
Admittedly verbal similarities exist between the counts and the respective disclosures of the parties. However, to stop here is to violate the spirit of 35 U.S.C. § 135 which authorizes interferences where two or more parties claim “the same subject matter.”
Thus the issue cannot be decided here in the rarified atmosphere of claim semantics. Instead, it must be decided at the down to earth level of what the parties disclosed as “the gist” of their respective inventions. Cf. Hansgirg v. Kemmer, 102 F.2d 212, 26 CCPA 937.3 While an “unambiguous” count may be interpreted without resort to the specification, the counts here are not of this type. Considering the wording of the counts, particularly the term “reference” surfaces, and the arguments of the parties, it is clear that different meanings are ascribed to that term by the parties when interpreting the count. When resort is had to the specifications, the latent ambiguity in the counts becomes apparent.
For appellee to prevail here, it is necessary to find such similarities of the inventions as to support the conclusion that the parties are asserting inventor-ship of substantially the same invention. 35 U.S.C. § 135.
There is no dispute that both parties were concerned with the same problem: how to construct an interchangeable multiple transducer head mounting unit which would not cause distorted signals to be read from the tape when the heads were . changed. Both parties disclose structures in which one mounting unit could be substituted in precisely the same position as another unit. As background it is clear that prior to the work of either party as it was old in this art to construct a transducer head from two core sections wherein the core sections are separated by a recording/reproducing gap. Also, multiple transducer heads were old in the art.
The “gist” of the inventions disclosed by McCutchen and by Oliver is more readily understood by reference to the drawings from their specifications which show preferred embodiments of their respective inventions.
*612
*613McCUTCHEN, JR.
Oliver’s disclosed invention by reference to Fig. 5 is seen to embody ten core sections which are placed in each of two housings 13. The two housings when joined together, as shown in Fig. 2, form a mounting unit 10. Oliver teaches one to place the core sections in each housing, and then pour an epoxy resin around *614the core sections to hold them in position. Thereafter, insofar as it is relevant here, two grinding operations are performed on the mounting unit: (1) grind “entire inner surface 28 * * * true and flat;” and (2) grind “back surface 29 of housing 13 * * * to a fixed dimension, parallel to polished inner surface 28.” After assembly of two housings in one mounting unit, this unit may be placed into holder 40, Fig. 2, and positioning, as relevant here, is achieved through the cooperation of “the precisely machined back surface 29” against “the likewise precisely machined inner” surface of holder 40 of the tape unit. The specification states:
* * * this type of construction renders alignment of the head gap with respect to the channels on the magnetic tape a simple procedure inasmuch as the outer surfaces of the metallic housings can be precisely machined parallel with the gaps of the heads, and to the same dimensions.
Now, considering McCutchen’s invention, we find in Fig. 3 that a bracket with two frame members, 10 and 30, is disclosed. According to the specification, “The second frame member 30 in the bracket is essentially identical to the above-described frame member 10, except that it is substantially shorter at each end.” After inserting the core sections in the frame members, each assembly is lapped. The two frame members are then placed together and a potting material is poured around the core sections. The specification states:
With the parts secured together in this fashion, it will be apparent from Figs. 3 and 4 that the broad lapped front faces 10a' and 10b' on the frame member 10 are exposed at either end of the head unit and serve as reference surfaces aligned with the recording/reproducing gaps of the individual heads in the unit. This novel structural feature of the present head unit may be used advantageously when mounted as shown in Figs. 3 and 4. * * *
In actual practices, rather than starting with different sized frame members 10 and 30, it may be preferable to have these frame members identical initially. Then, after the frame and pole piece sub-assemblies have been assembled together, the ends of one of these identical frame members are cut off to leave the front faces on the other frame member exposed at either end, resulting in the head unit shown in Figs. 3 and 4.
Comparing the two inventions as thus disclosed, can it be said that Oliver discloses the gist of the McCutchen invention? Our answer is “no.” McCutchen, in his solution to the problem, performs fewer operations than Oliver. If the operations disclosed by McCutchen are performed according to the Oliver disclosure the problem remains unsolved. To complete his solution to the problem, Oliver must perform additional steps, i. e., the back surface 29 of housing 13 must be ground to a fixed dimension, parallel to the polished inner surface 28.
An examination of the testimony presented supports the foregoing conclusion. Oliver testified that the solution to the problem was found in utilizing two reference surfaces cooperating with the lapped pole tips. Witness Ackley, who “physically made all of the parts that went into the heads” under “Oliver’s direction,” testified in detail as to the lap finish of the inner and outer surface (utilizing a monochromatic light source and an optical light flat for checking); and the tolerances as to thickness (one-thousandth of an inch) and parallelism (one-tenth of a thousandth) in the finished article. Accuracy in parallelism was preferred over accuracy in thickness and there was no exposed reference surface co-planar with the lapped pole tip surfaces. Testimony offered by McCutchen is in complete accord with the Mc-Cutchen disclosure. Thus the parties solved a common problem confronting the art by different approaches resulting in different inventions.
*615Oliver argues in his brief as follows: * * * In the McCutchen et al patent * * * the mounting approach chosen is to provide mounting surfaces * * * on the head unit finished coplanar with reference to the coplanar reference surfaces. In the Oliver application * * * the mounting approach chosen is to provide mounting surfaces on the head unit finished parallel with reference to the coplanar reference surfaces. Both McCutchen et al and Oliver abut their thus provided mounting surfaces against a cooperating surface on the tape transport equipment to permit rapid and accurate mounting on the head unit on the head unit on the tape transport equipment. * * *
From the foregoing, it should be evident that both Appellants and Appellee use the same basic solution for solving the mounting problem. That is, both parties provide a coplanar reference surface as a convenient reference of the gap plane, * *
In view of the fact that appellee was confronted with the real problems of maintaining dimensional thickness in relation to parallelism, absent in McCutchen’s device, we do not agree with the position of appellee that “Appellants and Appellee use the same basic solution for solving the mounting problem.”
Since we find the gist of the two inventions to be different, McCutchen’s motion, filed September 29, 1961, to dissolve the interference should have been granted for the reason stated therein that “The party Oliver has no right to make the claims forming the counts in issue, and his application contains no support for the claims.” In denying this motion, the requirement that the disclosure must teach the “gist” of the invention seems to have been ignored. Instead, there appears to have been a slavish examination of each word of the count in minute detail without considering the over-all meaning of these words as used in the parties’ respective specifications. This ignores the basic concept of the Henderson case, supra.
MeCutchen’s motion to dissolve pointed out in pertinent part that:
Oliver forms his head in two halves as many persons previously have done. He puts two similar head valves together on either side of a shim 33, which leaves two flanges 37 protruding out the side of his head. He does not say that these flanges are used for locating precisely the gap of the transducer head(s). Quite the contrary— Oliver states at page 2 (lines 28 to 30) and page 3 (lines 1 to 3) that his “type of construction renders alignment of the head gaps with respect to the channels of the magnetic tape a simple procedure inasmuch as the outer surfaces of the metallic housings can be precisely machined parallel with the gaps of the heads, and to the same dimensions”. This is exactly what the patentees’ invention eliminates.
******
Thus, by Oliver’s own words, it is the back 29 and the side 31 of his head which are used to align his head. The front faces of the flanges 37 are not used in any way to mount the head in its holder.
The primary examiner, apparently without regard to the “gist” of the respective inventions, referred in his decision on this motion to the literal language of the counts. He stated:
Upon examination of Count 1 nowhere is there seen the limitation that requires the references surfaces to be contacted by a corresponding reference surface forming part of the data handling equipment. Since said limitation is not clearly included in the Count it will therefore not be read into the Count of this interference * * *.
It is further noted that nowhere in Count 1 does it state that the “refererence surfaces”, themselves, are used to align the head, or mount the head. These also are limitations not included in Count 1 and therefore will not be read into said Count.
The wording “reference surfaces” means just that; the wording is not *616ambiguous and it will be given its broadest interpretation in relation to its import. It is noted that surface 28 (see Fig. 3) of the Oliver application is used as a reference surface for back surface 29 (see lines 6-9, page 6), which positions the head structure with reference to its holder (see lines 1-5, page 8). In view of the above, it would be natural and logical to identify the surfaces 28, of Oliver, as “reference surfaces.”
It is plain from the above that the test of the Henderson case, supra, was ignored. To avoid an interference, it appears the primary examiner would require that McCutchen’s claims recite that the broad reference surfaces contact the machine and that these surfaces align the head in the machine. We do not agree with this reasoning as the claim to the transducer head unit need not recite how the unit operates nor may the claim be interpreted to define only part of a unit as Oliver would have us do.
The board in affirming the examiner also appears to have ignored the test referred to in the Henderson case, supra, that the “gist” of the respective inventions must be the same. It accepted the reasoning of the primary examiner and added that the McCutchen claim did not expressly state that the reference surfaces were exposed, ignoring the long established rule of law that Oliver is entitled only to a reasonable interpretation of the copied claims.
Oliver argues that the counts do not require that the reference surface coplanar with the lapped pole tips be exposed. McCutchen in his specification discloses no less than eleven times that his reference surfaces are exposed, that they serve as aligning means, and that they abut against the machine.
During prosecution, McCutchen, to overcome prior art references, argued:
Applicants’ invention lies in the provision of a magnetic transducer head having an “air gap” and a support or bracket for the head which has an exposed surface at one side of the head which is aligned with the gap.
****■« *
In order to facilitate the change of transducer heads in precision equipment of the aforesaid types, applicants have provided heads having precision aligned transducer gaps, and these gaps are precision aligned with one or more “outrigger” surfaces which lie in the plane of the transducer gap. ******
Rettinger does not show an exposed planar surface aligned with the head gaps, and mounting the head assembly of Rettinger in Saegar’s bracket does not supply such an “outrigger” surface. * * *
******
Such a feature which is essential to applicants’ head and which is claimed in each and every claim is completely missing from Rettinger's head.
Applicants cannot find a single reference surface in the Rettinger head which is co-planar with the plane of the gaps of the head. If there is such a surface will the Examiner please refer to it by reference number if possible, or by some other description.
****** Applicants’ claims call for the head support to have an exposed surface aligned co-planar with the transducing gap. The prior art does not show or describe this structual feature. Consequently the claims should be allowed.
The Patent Office removed the rejection based on prior art references and the claims, in view of McCutchen’s arguments, were allowed. Such arguments relied on by the applicant and accepted by the Patent Office to avoid prior art references should be considered in interpreting the claims. Considering the respective inventions and the McCutchen specification and file wrapper, we think the McCutchen co-planar “reference surfaces” are exposed. Oliver does not disclose such “reference surfaces.” Since we find this to be a necessary feature of the invention as defined by the counts, the decision of the board is reversed.
Reversed.
. Application serial No. 530,014, filed August 23, 1955, assigned to National Cash Register Co.
. Patent No. 2,888,522, granted May 26, 1959, on an application filed September 6, 1955, assigned to Clevite Corporation.
. Therein the court stated, 102 F.2d at 26 CCPA at 940, applied recently in In re Spencer, 273 F.2d 181, 47 CCPA 751:
Where one copies a claim from an inadvertently issued patent it should clearly appear that his application disclosed the invention either expressly or inherently. See McKee v. Noonan, 86 F.2d 986, 24 CCPA Patents, 784; Lindley v. Shepherd, 58 App.D.C. 31, 24 F.2d 606.