From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Sat, 18 Jul 2026 07:44:40 -0700 Received: from mail-ot1-f55.google.com ([209.85.210.55]) by mail.fairlystable.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1wl6HQ-0002bc-2r for bitcoindev@gnusha.org; Sat, 18 Jul 2026 07:44:40 -0700 Received: by mail-ot1-f55.google.com with SMTP id 46e09a7af769-7e9ee20bde0sf5414425a34.2 for ; Sat, 18 Jul 2026 07:44:39 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1784385873; cv=pass; d=google.com; s=arc-20260327; b=tASO5NILV77Brzqe/S15E+2y5aCSGJm+zHF6BMUB3yGDtm5YHYZLJKwpoyHFHligX5 dn7BKzjrv+7qm9Ktzva/FXbk8cIzU6bGCJHZD3La1lseKl/wUFNB9NhAmW18/aH3bW9S GdFAvlC5e0L8P6Y4qjhVUczogvBnsKtNWRDQE0oeEA70c8qHIguLUNxjDM/kNfWqqaoL mFUR38HjiK1HJwyaBxVh3KJJEYnjKZdfWVD8E5yFQrqBxx5pClXvQcRtUFRhxxjlxTzW P3gkoKHm31lXTSP5Bobc5TVmOGNKaogeVz03o7XuF82CxFPE4EPKlvwMJrFqj7Eu21gW 1NqQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post :list-id:mailing-list:precedence:reply-to:mime-version:feedback-id :message-id:subject:from:to:date:dkim-signature; bh=o6/X8vt5s/UtDtt4X98TgP6kL8kHz8eFPCSkjlm0KVw=; fh=n+s2qA4Ma3ctm4ACiQE/YZLUqgQEPGbPaiwK50Yuao8=; b=NlBfyWNgmPiPMfE9m0K96mQ9xAhuX/YvlrsP5UjO8d9JKNLFaueGQ1gskR4gxl+CR0 iL3+5Qqx2XaWyU6T4PSbpTvgMiNLUE2SOwr4d+cCLFqknckJVZiJW/7iISyVjOvPgVhl ZJTYoId9H3aTasErF+YMVK6T522HqYDkLT8BMbgPj6626LGlj7ubpKi7VaHMnEhtFNnK UDvqkX5vCdpcTJs317lP7b+C2/A1RNmC7af46YKEfX36XFTwzX2fu0/o6hoOmfVbrJAU irF/1GVAEwsd6DPC0J+C5fpODQDDWFQEov674+X5OX4ZKyiLwOjX5MFqnQYhEbU8C5eO 1XlQ==; darn=gnusha.org ARC-Authentication-Results: i=2; gmr-mx.google.com; dkim=pass header.i=@protonmail.com header.s=protonmail3 header.b=rUMnZNRK; spf=pass (google.com: domain of fjahr@protonmail.com designates 109.224.244.18 as permitted sender) smtp.mailfrom=fjahr@protonmail.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=protonmail.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlegroups.com; s=20251104; t=1784385873; x=1784990673; darn=gnusha.org; h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post :list-id:mailing-list:precedence:reply-to :x-original-authentication-results:x-original-sender:content-type :mime-version:feedback-id:message-id:subject:from:to:date:from:to:cc :subject:date:message-id:reply-to:content-type; bh=o6/X8vt5s/UtDtt4X98TgP6kL8kHz8eFPCSkjlm0KVw=; b=Acm0FXZ7e7geAXViuQg23xJrA+vHgCVY/r8u97lTDnjTTmTc1yaoknSrcHDxKXkrW1 xfOmtaGHAGOq+tcvlbBYrpqBcfsr0r7j2m6J/gIfJPTDmzHoaXye7JXKrz00IXF+/kv5 BraaEQbeJf2M1tVc68y81BGCrwxrNoGEXb+Q17Bf+5gb7EW+PGAEdKJtfcN062xzgJsk jlAWf8IoQed5zLkSF5KZcr92NtTOs7MDVBtKcXTLmQFnIrMjF/U6RVGMIShaADMGv4IG 5QC2mumLV3K//Z3eHA9w+IDhusQJyWhqFNl9YXrDKXNq2JtND6XlhlHcbovLK6vyS+ES e8Cw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784385873; x=1784990673; h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post :list-id:mailing-list:precedence:reply-to :x-original-authentication-results:x-original-sender:content-type :mime-version:feedback-id:message-id:subject:from:to:date :x-beenthere:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=o6/X8vt5s/UtDtt4X98TgP6kL8kHz8eFPCSkjlm0KVw=; b=VulcxPaagDm0ie7Kv4XbQZjPjGHVDDKrJ15mDQxo4nS6HHhBi9300ddWAXE5Lb4aX4 81DuNiQGglGP3FVI5o0heaFD4PyqtnkoCRQhwbnY0bh/A0z4qZM0D2QIMaoYIRj7c0T+ W0Kkkx9MXbLA0wqCC0C/PNQJ9KqA+iyBXfmPR3L01E+Ev/n9FokN0lBAlUg1ywbtUL/5 9Nvy6IBm2lnlsIeNbZQJEedkLc7HCmFxgr6qcxxuOUg54mRJDDA6Ht+3fPCoSTLJpWWf 59Jfnn415EfRcmsBvNTQDUNvJdQw0a3RmGKgQXmkm+c47FhnOtkDZ2qKAPvLKjHXZZru YK/A== X-Forwarded-Encrypted: i=2; AHgh+Rol3iUJZ5YT71u/m1wCvxtME1rt8UpUsGT2b2WwwUjne5PTk+Lacvq0gvohd7MIQiwOeqrJjEug0eWD@gnusha.org X-Gm-Message-State: AOJu0YyuJ+4jVXaQ75A2QBSYYpflW9F3rGSQPa/JFE+l9DoEM7Dty07A 3X9NcioBn0PF+eKazwjMVniDwMQNurQG48LlgcObD2BvDVihiBZpJS5P X-Received: by 2002:a4a:ec43:0:b0:6a1:22cd:8ffd with SMTP id 006d021491bc7-6a53683be20mr2965832eaf.34.1784385873439; Sat, 18 Jul 2026 07:44:33 -0700 (PDT) X-BeenThere: bitcoindev@googlegroups.com; h="Aa7YSPRKMED78AcAkxqjdTavQqe+Zjso1e4wIsgajt1g/v2CEQ==" Received: by 2002:a05:6820:189a:b0:6a3:d777:c4f6 with SMTP id 006d021491bc7-6a3eefa6361ls1514536eaf.1.-pod-prod-02-us; Sat, 18 Jul 2026 07:44:28 -0700 (PDT) X-Received: by 2002:a05:6808:1645:b0:487:52de:3428 with SMTP id 5614622812f47-4a4d05135a8mr3648022b6e.24.1784385868149; Sat, 18 Jul 2026 07:44:28 -0700 (PDT) Received: by 2002:a05:6808:8d9:b0:497:d3cb:4050 with SMTP id 5614622812f47-4a410595fbcmsb6e; Sat, 18 Jul 2026 05:39:16 -0700 (PDT) X-Received: by 2002:a05:6830:a8f:b0:7e9:e342:3e0 with SMTP id 46e09a7af769-7eda09444cfmr3492404a34.18.1784378355323; Sat, 18 Jul 2026 05:39:15 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1784378355; cv=none; d=google.com; s=arc-20260327; b=hgX9GGZdr/ZwdlD9NsNz6gZrOQ3bi5KQAsbKIFmRTJlbh2N81Nmyzi/8e9zdF3lDzN fTCAmbQVAmtYg1u/ec5O9RTrJIWgW9VaHd0yo/zmpOhlIGpiqSgE5JsJRT/cAnYq60n0 dQlO3/twYOEumdlGciAPi0qjlkMrD9W6ZPLHiML++llsCvnbs6Vw3YBSG5/zRRVa2i+q 7SMLXuFsIMB3IafdaYUq7PZLC+ZwpH1f9dSB/MjMMB4ldjMlNOJSy6IpwI871D4ZHCJI WZkAyHoOOsIMN94no6tUActMMn9DBOIFPmz54z2flNP5A0/JI6nosW8JzxXvbkkhUJtk OMNw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=mime-version:feedback-id:message-id:subject:from:to:date :dkim-signature; bh=LxymudnfI9O/rokEia9xnc33JYKWw0omMU1neFfD6D4=; fh=DMP0F9ULS1guKiqimntQRCN8ZraraesEgQuVcn7F0Z0=; b=gN92x+9QuyISLvROE+aBXHZdhKEh1/oMqTVekNcAnxmTskc18YL9HR8Go7P3XBt/SB i24dsT3f8GiOfMA5ZngE+rOr0zkjamlfLcbgPcnCScMGvcX713ZJHWzouJlqpv4v1ZHw wNMq+ONYpBOXikkAxfZeHW6I3/R25vYgpHI42LysTMoVuNXBwwNEvHQKmwMdYK+ZYZVx FujfOn9ylUnqP/nLRxkTbnbCOw/QldhodzsCVL0tNLdfgJoptDFc1cZgTyTILQbbTubA QPeBCuahigaNjRpdLKUiHUvjFKUp8TcR5bqZSdI8Bj04QB8pJDyOePaAVk5vhLHLb7IK OLfQ==; dara=google.com ARC-Authentication-Results: i=1; gmr-mx.google.com; dkim=pass header.i=@protonmail.com header.s=protonmail3 header.b=rUMnZNRK; spf=pass (google.com: domain of fjahr@protonmail.com designates 109.224.244.18 as permitted sender) smtp.mailfrom=fjahr@protonmail.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=protonmail.com Received: from mail-24418.protonmail.ch (mail-24418.protonmail.ch. [109.224.244.18]) by gmr-mx.google.com with ESMTPS id 46e09a7af769-7edaf9307aasi174912a34.4.2026.07.18.05.39.15 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Jul 2026 05:39:15 -0700 (PDT) Received-SPF: pass (google.com: domain of fjahr@protonmail.com designates 109.224.244.18 as permitted sender) client-ip=109.224.244.18; Date: Sat, 18 Jul 2026 12:39:08 +0000 To: Bitcoin Development Mailing List From: "'Fabian' via Bitcoin Development Mailing List" Subject: [bitcoindev] BIP draft: CISA for Taproot Key Path Spends Message-ID: Feedback-ID: 5067558:user:proton X-Pm-Message-ID: 8ee1b3e70d6dffe57d407d58014aa508570d21e9 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="b1=_z3Kp1SK6hURaK5PSxT1nzuQDDSiS98iXCByOoDyMI" X-Original-Sender: fjahr@protonmail.com X-Original-Authentication-Results: gmr-mx.google.com; dkim=pass header.i=@protonmail.com header.s=protonmail3 header.b=rUMnZNRK; spf=pass (google.com: domain of fjahr@protonmail.com designates 109.224.244.18 as permitted sender) smtp.mailfrom=fjahr@protonmail.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=protonmail.com X-Original-From: Fabian Reply-To: Fabian Precedence: list Mailing-list: list bitcoindev@googlegroups.com; contact bitcoindev+owners@googlegroups.com List-ID: X-Google-Group-Id: 786775582512 List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , X-Spam-Score: -1.0 (-) --b1=_z3Kp1SK6hURaK5PSxT1nzuQDDSiS98iXCByOoDyMI Content-Type: text/plain; charset="UTF-8" Hi list, I would like to share a BIP draft for transaction-wide cross-input signature aggregation (CISA). It introduces a new witness version, which enables Taproot-style key path spending where inputs can aggregate their signatures. Each input chooses between half-aggregation, full-aggregation, or an explicit opt-out via a marker byte in its witness. The aggregation schemes themselves are specified in the previously shared BIP 458 (half-aggregation) and BIP 459 (full-aggregation) drafts. Script path spending follows BIP 341/342 unchanged. The BIP draft text can be found here: https://github.com/fjahr/bips/blob/cf0d4f2142cd0504b16e86739167b1f7ab9a3a06/bip-XXXX.mediawiki For inline comments, I have opened a mock pull request on my BIPs repo fork: https://github.com/fjahr/bips/pull/6 Feedback of any kind is much appreciated. Best,Fabian -- You received this message because you are subscribed to the Google Groups "Bitcoin Development Mailing List" group. To unsubscribe from this group and stop receiving emails from it, send an email to bitcoindev+unsubscribe@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/Qc_VmkfXgE8KHBfUnUB-hdWF1QOYv6zshzI7WEv_hvqJ6O_4zssJ4X2T2Di79I3TqHQvRDXsFtD8os5M44wrbB61M1LD_-GDRGYEagoHsV4%3D%40protonmail.com. --b1=_z3Kp1SK6hURaK5PSxT1nzuQDDSiS98iXCByOoDyMI Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
=
Hi list,

I would l= ike to share a BIP draft for transaction-wide cross-input
= signature aggregatio= n (CISA). It introduces a = new witness version,
which enables Taproot-style key path spending where&= nbsp;inputs can
aggregate their signatures.

Each input chooses between half-aggregation, = full-aggregation, or an
explicit opt-out via a marke= r byte in its witness.
The aggregation schemes themselves are specified in the prev= iously
shared BIP 458 (half-aggregation) and BIP 459= (full-aggregation)
drafts. Script path spending fol= lows BIP 341/342 unchanged.

The BIP d= raft text can be found here:

For inline comments,= I have opened a mock pull request on my BIPs
repo f= ork:

Feedback o= f any kind is much appreciated.

Best,=
Fabian

--
You received this message because you are subscribed to the Google Groups &= quot;Bitcoin Development Mailing List" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to bitcoind= ev+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/= Qc_VmkfXgE8KHBfUnUB-hdWF1QOYv6zshzI7WEv_hvqJ6O_4zssJ4X2T2Di79I3TqHQvRDXsFtD= 8os5M44wrbB61M1LD_-GDRGYEagoHsV4%3D%40protonmail.com.
--b1=_z3Kp1SK6hURaK5PSxT1nzuQDDSiS98iXCByOoDyMI--