DETAILED ACTION
A response was received on 06 March 2026. By this response, Claims 8-13 have been canceled. No claims have been amended or added. Claims 1-7 and 14-20 are currently pending in the present application.
Election/Restrictions
Applicant’s election without traverse of Group I in the reply filed on 06 March 2026 is acknowledged.
Applicant has canceled Claims 8-13, corresponding to group II, resulting in a constructive election of Group I by optional cancellation of claims. See MPEP § 818.02(c).
Claim Objections
Claims 1, 2, and 14 are objected to because of the following informalities:
In Claim 1, line 3, the commas before and after “the hardware wallet device” should be deleted. In Claim 1, line 19, in the phrase “one or more additional removable authentication device”, “device” should read “devices” for agreement with “one or more”.
In Claim 2, line 3, the comma after “connecting” should be deleted.
In Claim 14, line 25, in the phrase “one or more additional removable authentication device”, “device” should read “devices” for agreement with “one or more”.
Appropriate correction is required.
A series of singular dependent claims is permissible in which a dependent claim refers to a preceding claim which, in turn, refers to another preceding claim.
A claim which depends from a dependent claim should not be separated by any claim which does not also depend from said dependent claim. It is noted that Claim 5 is separated from Claim 2 from which it depends by Claim 4, which does not depend from Claim 2. It should be kept in mind that a dependent claim may refer to any preceding independent claim. In general, applicant's sequence will not be changed. See MPEP § 608.01(n).
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-7 and 14-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites “a number of stored secret shares on the hardware wallet device” in line 12. Although the claim recites storing a secret share in lines 10-11, it is not clear when other secret shares may have been stored, which appears to constitute a gap in the claim. The claim additionally recites “displaying a message…instructing a user to physically attach one or more additional removable authentication device[s]” but does not include steps in which the additional devices are attached in order to obtain sufficient additional shares to meet the threshold, as would be required to recover access to the wallet as recited in the preamble in line 1. Therefore, this constitutes an omission of essential subject matter as per MPEP § 2172.01. See also paragraphs 0059-0060 of the specification. The above ambiguities render the claim indefinite.
Claim 3 recites “connected sequentially or in series” in line 2. The distinction between “sequentially” and “in series” is not clearly defined in the claims or specification.
Claim 5 recites “the removable authentication device” in line 8. It is not clear to which of the plural removable authentication devices this limitation is intended to refer.
Claim 14 recites “a number of stored secret shares on the hardware wallet device” in line 15. Although the claim recites storing a secret share in lines 12-13, it is not clear when other secret shares may have been stored, which appears to constitute a gap in the claim. The claim additionally recites “displaying a message…instructing a user to physically attach one or more additional removable authentication device[s]” but does not include steps in which the additional devices are attached in order to obtain sufficient additional shares to meet the threshold, as would be required to provide access to the wallet as recited in the preamble in line 1. Therefore, this constitutes an omission of essential subject matter as per MPEP § 2172.01. See also paragraphs 0059-0060 of the specification. The above ambiguities render the claim indefinite.
Claim 16 recites “connected sequentially or in series” in line 2. The distinction between “sequentially” and “in series” is not clearly defined in the claims or specification.
Claim 18 recites “the removable authentication device” in line 9. It is not clear to which of the plural removable authentication devices this limitation is intended to refer.
Claims not explicitly referred to above are rejected due to their dependence on a rejected base claim.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 2, 4-6, 14, 15, and 17-19 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Cheng et al, US Patent Application Publication 2019/0280864 (cited by Applicant).
In reference to Claim 1, Cheng discloses a method that includes connecting a hardware wallet device to a physically attached removable authentication device in communication with the hardware wallet device (paragraphs 0091, 0096, 0100, 0103, portable HSM corresponds to removable authentication device, offline HSM corresponds to hardware wallet); receiving by a user input a PIN sequence and comparing by the removable authentication device the PIN sequence to a PIN stored on the removable authentication device (paragraphs 0091, 0101, 0105, 0182, receiving PIN for authentication, i.e. comparison); retrieving a secret share from the removable authentication device if the stored PIN and PIN sequence match and storing the secret share on the hardware wallet device (paragraphs 0091-0092, 0105-0106, exporting share when PIN is authenticated); determining if a number of stored secrets meets or exceeds a first threshold (paragraph 0183, 0186, number of shares sufficient to recover the master key corresponds to threshold; see also paragraphs 0235-0236, minimum number of shares, and paragraph 0267, checking number of shares); if the number meets or exceeds the threshold, applying a secrets sharing technique to the stored secret shares to recover a seed value and storing the seed value on the hardware wallet device (paragraph 0269, key recovered if correct number of shares provided); and if the number is below the threshold, displaying a message instructing a user to attach one or more additional removable authentication devices to the hardware wallet device (paragraph 0268, warning message if incorrect number of shares; paragraph 0153, additional shares can be requested which would be on additional portable HSM).
In reference to Claims 2 and 5, Cheng further discloses connecting one or more additional removable authentication devices (paragraph 0153, additional shares requested), and receiving a further PIN sequence and comparing the further PIN sequence to a further PIN stored on the additional removable authentication device (paragraphs 0091, 0101, 0105, 0182, receiving PIN for authentication, i.e. comparison, each user/share/device has own PIN), retrieving and storing a further secret share (paragraphs 0091-0092, 0105-0106, exporting share when PIN is authenticated), determining that the number of shares stored now meets or exceeds the first threshold (paragraph 0183, 0186, number of shares sufficient to recover the master key corresponds to threshold; see also paragraphs 0235-0236, minimum number of shares, and paragraph 0267, checking number of shares), and applying the secrets sharing technique to the stored secret shares to recover the seed value and store the seed value on the hardware device (paragraph 0269, key recovered if correct number of shares provided).
In reference to Claim 4, Cheng further discloses that the stored PIN is not revealed to the hardware wallet device (paragraph 0105, separate PIN entry device, i.e. PIN only entered on PED and not revealed to offline HSM).
In reference to Claim 6, Cheng further discloses Shamir’s secret sharing method (paragraph 0092).
Claims 14, 15, and 17-19 are directed to a hardware wallet device having functionality corresponding substantially to the methods of Claims 1, 2, and 4-6, and are rejected by a similar rationale, mutatis mutandis.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 3 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Cheng in view of Gaudet et al, US Patent Application Publication 2013/0291056 (cited by Applicant).
In reference to Claims 3 and 16, Cheng discloses everything as detailed above with respect to Claims 2 and 15. However, Cheng does not explicitly disclose that the additional devices are connected sequentially or in series. Gaudet discloses a method that includes connecting removable authentication devices sequentially or in series to recover a quorum key (see paragraphs 0032-0034, quorum must be established in a particular order). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Cheng to include the sequential/series connection of the devices to cause the sequential/series retrieval of shares as taught by Gaudet, in order to allow application of different policies depending on differing security levels (see Gaudet, paragraph 0024).
Claims 7 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Cheng in view of Bakker, European Publication EP 2662818.
In reference to Claims 7 and 20, Cheng discloses everything as detailed above with respect to Claims 1 and 14, and further discloses notifying a trusted server of a seed restoration attempt (paragraph 0247, using key recovery utility), providing a denial message to the wallet device (paragraph 0155), and interrupting the method and denying recovery of the seed value (paragraphs 0252-0253). However, Cheng does not explicitly disclose transmitting a rejection message to a user platform and receiving a denial message from the user platform. Bakker discloses a method that includes transmitting a rejection message to a user platform (paragraph 0045-0048, rejection message 204, additional message corresponds to denial message) and receiving a denial message from the user platform (paragraph 0049). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Cheng to include the rejection and denial messages of Bakker, in order to provide a reason for the denial (see Bakker, paragraph 0045).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Raevsky et al, US Patent 10790976, discloses systems for recovering a cryptocurrency wallet.
Carmignani et al, US Patent 11101986, discloses systems for recovering a cryptowallet seed using Shamir’s secret sharing.
Black et al, US Patent 11216809, discloses systems for restoring a wallet using split keys.
Chang et al, US Patent 12425203, discloses methods for using secret sharing to recover a seed phrase for a cryptocurrency wallet.
Chen et al, US Patent Application Publication 2022/0271933, discloses a method that uses secret sharing to recover cryptocurrency wallet recovery phrases.
Jakobsen et al, US Patent Application Publication 2025/0104028, discloses a method for performing emergency recovery of a cryptocurrency wallet using secret sharing.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Zachary A Davis whose telephone number is (571)272-3870. The examiner can normally be reached Monday-Friday, 9:00am-5:30pm, Eastern Time.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Rupal D Dharia can be reached at (571) 272-3880. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Zachary A. Davis/Primary Examiner, Art Unit 2492
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