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From: jeremy <jeremy.l.rubin@gmail.com>
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Subject: Re: [bitcoindev] Re: [BIP Proposal] Limit ScriptPubkey Size >= 520
 Bytes Consensus.
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I think that this type of rule is OK if we do it as a "sunsetting"=20
restriction -- e.g. a soft fork active for the next N blocks (N =3D e.g. 2=
=20
years, 5 years, 10 years).

We may yet find a compelling use for larger scriptpubkeys, and to me the=20
interactions between different key types is non-obvious.

An example of where big SPK is valuable v.s. e.g. Taproot, Segwit, P2SH is=
=20
if there is one big script path required in a two-tx protocol, and the=20
inclusion price must be paid by the proposed of the first tx. In this case,=
=20
we'd want the inclusion guaranteed by the first tx and then the cost isn't=
=20
paid (other than satisfaction cost).

You can argue against this example probably, but it is worth considering=20
that absence of evidence of use is not evidence of absence of use and I=20
myself feel that overall our understanding of Bitcoin transaction=20
programming possibilities is still early.  If you don't like this example,=
=20
I can give you others (probably).

As such, I'm NACK on a permanent restriction on what could be a valuable=20
use. But I do think it could be reasonable to set up an auto-renewing=20
restriction on a 1-2 year basis, and allow it to be removed if we later=20
decide we want them.

(N.B. this differs from past temporary soft fork proposals as it's a=20
restriction on something we think no one will do that we eventually lift,=
=20
rather than removing after a time an opcode that we expect people would=20
want to rely on.)

On Friday, October 3, 2025 at 7:03:09=E2=80=AFAM UTC-4 moonsettler wrote:

> Hi Floppy,
>
> There are only weak arguments for this proposal to extend to OP_RETURN, a=
t=20
> least nothing I would normally entertain;
> but also there are weak arguments to make an exception for OP_RETURN=20
> explicitly.
>
> People could just add many OP_RETURNs to a transaction, that makes it mor=
e=20
> cumbersome and marginally more expensive.
>
> BR,
> moonsettler
>
>
> On Friday, October 3rd, 2025 at 10:58 AM, /dev /fd0 <alice...@gmail.com>=
=20
> wrote:
>
> > Hi portlandhodl,
> >=20
> > We can't predict future usage, so it would be great if this was=20
> restricted to OP_RETURN. While there is no real use for a scriptPubKey=20
> larger than 520 bytes as shown in the data you shared, it is possible tha=
t=20
> users may create more OP_RETURN outputs after this change. It does not=20
> affect the UTXO set but will cost more and economically discourage the us=
e=20
> of multiple OP_RETURN outputs.
> >=20
> > /dev/fd0
> > floppy disk guy
> > On Friday, October 3, 2025 at 3:29:24=E2=80=AFAM UTC+5:30 PortlandHODL =
wrote:
> >=20
> > > Proposing: Softfork to after (n) block height; the creation of=20
> outpoints with greater than 520 bytes in the ScriptPubkey would be=20
> consensus invalid.
> > >=20
> > > This is my gathering of information per BIP 0002
> > >=20
> > > After doing some research into the number of outpoints that would hav=
e=20
> violated the proposed rule there are exactly 169 outpoints. With only 8=
=20
> being non OP_RETURN. I think after 15 years and not having discovered use=
=20
> for 'large' ScriptPubkeys; the reward for not invalidating them at the=20
> consensus level is lower than the risk of their abuse.
> > >=20
> > > - Reasons for
> > > - Makes DoS blocks likely impossible to create that would have any=20
> sufficient negative impact on the network.
> > > - Leaves enough room for hooks long term
> > > - Would substantially reduce the divergence between consensus and=20
> relay policy
> > > - Incredibly little use onchain as evidenced above.
> > > - Could possibly reduce codebase complexity. Legacy Script is largely=
=20
> considered a mess though this isn't a complete disablement it should redu=
ce=20
> the total surface that is problematic.
> > > - Would make it harder to use the ScriptPubkey as a 'large'=20
> datacarrier.
> > > - Possible UTXO set size bloat reduction.
> > >=20
> > > - Reasons Against
> > > - Bitcoin could need it in the future? Quantum?
> > > - Users could just create more outpoints.
> > >=20
> > > Thoughts?
> > >=20
> > > source of onchain data
> > >=20
> > > PortlandHODL
> >=20
> > --
> > You received this message because you are subscribed to the Google=20
> Groups "Bitcoin Development Mailing List" group.
> > To unsubscribe from this group and stop receiving emails from it, send=
=20
> an email to bitcoindev+...@googlegroups.com.
> > To view this discussion visit=20
> https://groups.google.com/d/msgid/bitcoindev/842930fb-bede-408a-8380-776d=
4be4e094n%40googlegroups.com
> .
>

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I think that this type of rule is OK if we do it as a "sunsetting" restrict=
ion -- e.g. a soft fork active for the next N blocks (N =3D e.g. 2 years, 5=
 years, 10 years).<div><br /></div><div>We may yet find a compelling use fo=
r larger scriptpubkeys, and to me the interactions between different key ty=
pes is non-obvious.</div><div><br /></div><div>An example of where big SPK =
is valuable v.s. e.g. Taproot, Segwit, P2SH is if there is one big script p=
ath required in a two-tx protocol, and the inclusion price must be paid by =
the proposed of the first tx. In this case, we'd want the inclusion guarant=
eed by the first tx and then the cost isn't paid (other than satisfaction c=
ost).</div><div><br /></div><div>You can argue against this example probabl=
y, but it is worth considering that absence of evidence of use is not evide=
nce of absence of use and I myself feel that overall our understanding of B=
itcoin transaction programming possibilities is still early.=C2=A0 If you d=
on't like this example, I can give you others (probably).</div><div><br /><=
/div><div>As such, I'm NACK on a permanent restriction on what could be a v=
aluable use. But I do think it could be reasonable to set up an auto-renewi=
ng restriction on a 1-2 year basis, and allow it to be removed if we later =
decide we want them.</div><div><br /></div><div>(N.B. this differs from pas=
t temporary soft fork proposals as it's a restriction on something we think=
 no one will do that we eventually lift, rather than removing after a time =
an opcode that we expect people would want to rely on.)</div><div><div><br =
/></div></div><div class=3D"gmail_quote"><div dir=3D"auto" class=3D"gmail_a=
ttr">On Friday, October 3, 2025 at 7:03:09=E2=80=AFAM UTC-4 moonsettler wro=
te:<br/></div><blockquote class=3D"gmail_quote" style=3D"margin: 0 0 0 0.8e=
x; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">Hi Floppy=
,
<br>
<br>There are only weak arguments for this proposal to extend to OP_RETURN,=
 at least nothing I would normally entertain;
<br>but also there are weak arguments to make an exception for OP_RETURN ex=
plicitly.
<br>
<br>People could just add many OP_RETURNs to a transaction, that makes it m=
ore cumbersome and marginally more expensive.
<br>
<br>BR,
<br>moonsettler
<br>
<br>
<br>On Friday, October 3rd, 2025 at 10:58 AM, /dev /fd0 &lt;<a href data-em=
ail-masked rel=3D"nofollow">alice...@gmail.com</a>&gt; wrote:
<br>
<br>&gt; Hi portlandhodl,
<br>&gt;=20
<br>&gt; We can&#39;t predict future usage, so it would be great if this wa=
s restricted to OP_RETURN. While there is no real use for a scriptPubKey la=
rger than 520 bytes as shown in the data you shared, it is possible that us=
ers may create more OP_RETURN outputs after this change. It does not affect=
 the UTXO set but will cost more and economically discourage the use of mul=
tiple OP_RETURN outputs.
<br>&gt;=20
<br>&gt; /dev/fd0
<br>&gt; floppy disk guy
<br>&gt; On Friday, October 3, 2025 at 3:29:24=E2=80=AFAM UTC+5:30 Portland=
HODL wrote:
<br>&gt;=20
<br>&gt; &gt; Proposing: Softfork to after (n) block height; the creation o=
f outpoints with greater than 520 bytes in the ScriptPubkey would be consen=
sus invalid.
<br>&gt; &gt;=20
<br>&gt; &gt; This is my gathering of information per BIP 0002
<br>&gt; &gt;=20
<br>&gt; &gt; After doing some research into the number of outpoints that w=
ould have violated the proposed rule there are exactly 169 outpoints. With =
only 8 being non OP_RETURN. I think after 15 years and not having discovere=
d use for &#39;large&#39; ScriptPubkeys; the reward for not invalidating th=
em at the consensus level is lower than the risk of their abuse.
<br>&gt; &gt;=20
<br>&gt; &gt; -   Reasons for
<br>&gt; &gt;     -   Makes DoS blocks likely impossible to create that wou=
ld have any sufficient negative impact on the network.
<br>&gt; &gt;     -   Leaves enough room for hooks long term
<br>&gt; &gt;     -   Would substantially reduce the divergence between con=
sensus and relay policy
<br>&gt; &gt;     -   Incredibly little use onchain as evidenced above.
<br>&gt; &gt;     -   Could possibly reduce codebase complexity. Legacy Scr=
ipt is largely considered a mess though this isn&#39;t a complete disableme=
nt it should reduce the total surface that is problematic.
<br>&gt; &gt;     -   Would make it harder to use the ScriptPubkey as a =
9;large&#39; datacarrier.
<br>&gt; &gt;     -   Possible UTXO set size bloat reduction.
<br>&gt; &gt;        =20
<br>&gt; &gt; -   Reasons Against
<br>&gt; &gt;     -   Bitcoin could need it in the future? Quantum?
<br>&gt; &gt;     -   Users could just create more outpoints.
<br>&gt; &gt;=20
<br>&gt; &gt; Thoughts?
<br>&gt; &gt;=20
<br>&gt; &gt; source of onchain data
<br>&gt; &gt;=20
<br>&gt; &gt; PortlandHODL
<br>&gt;=20
<br>&gt; --
<br>&gt; You received this message because you are subscribed to the Google=
 Groups &quot;Bitcoin Development Mailing List&quot; group.
<br>&gt; To unsubscribe from this group and stop receiving emails from it, =
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/d/msgid/bitcoindev/842930fb-bede-408a-8380-776d4be4e094n%40googlegroups.co=
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842930fb-bede-408a-8380-776d4be4e094n%2540googlegroups.com&amp;source=3Dgma=
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4n%40googlegroups.com</a>.
<br></blockquote></div>

<p></p>

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