There's  an absurd fee (non-consensus) check already. Maybe that check can
be improved, but probably the wallet layer is more appropriate for this.
On Mar 3, 2016 16:23, "Henning Kopp via bitcoin-dev" <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> Hi,
> I think there is no need to do a hardfork for this. Rather it should
> be implemented as a safety-mechanism in the client. Perhaps a warning
> can pop up, if one of your conditions A) or B) is met.
>
> All the best
> Henning Kopp
>
>
> On Thu, Mar 03, 2016 at 05:02:11AM -0800, Alice Wonder via bitcoin-dev
> wrote:
> > I think the next hard fork should require a safety rule for TX fees.
> >
> >
> https://blockchain.info/tx/6fe69404e6c12b25b60fcd56cc6dc9fb169b24608943def6dbe1eb0a9388ed08
> >
> > 15 BTC TX fee for < 7 BTC of outputs.
> >
> > Probably either a typo or client bug.
> >
> > My guess is the user was using a client that does not adjust TX fee, and
> > needed to manually set it in order to get the TX in the block sooner, and
> > meant 15 mBTC or something.
> >
> > I suggest that either :
> >
> > A) TX fee may not be larger than sum of outputs
> > B) TX fee per byte may not be larger than 4X largest fee per byte in
> > previous block
> >
> > Either of those would have prevented this TX from going into a block.
> >
> > Many people I know are scared of bitcoin, that they will make a TX and
> make
> > a mistake they can't undo.
> >
> > Adding protections may help give confidence and there is precedence to
> doing
> > things to prevent typo blunders - a public address has a four byte
> checksum
> > to reduce the odds of a typo.
> >
> > This kind of mistake is rare, so a fix could be included in the coming HF
> > for the possible July 2017 block increase.
> >
> > Thank you for your time.
> >
> > Alice Wonder
> > _______________________________________________
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> > bitcoin-dev@lists.linuxfoundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
> >
>
> --
> Henning Kopp
> Institute of Distributed Systems
> Ulm University, Germany
>
> Office: O27 - 3402
> Phone: +49 731 50-24138
> Web: http://www.uni-ulm.de/in/vs/~kopp
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