It depends, but probably not; it seems "clearly too high"
Let us assume that Bob and Alice entered a contract along the lines of:
- Bob will not [do the thing]
- If Bob [does the thing], Bob will pay Alice $1 million
Note that unlike in a common-law jurisdiction, there is no need for reciprocal consideration, so that contract (which is all negatives for Bob) is legal.
Let us ignore possible liability towards third parties due to copyright or other concerns. If Bob does the thing, then refuses to pay, Alice will rely on Code civil, 1231-5:
Lorsque le contrat stipule que celui qui manquera de l'exécuter paiera une certaine somme à titre de dommages et intérêts, il ne peut être alloué à l'autre partie une somme plus forte ni moindre.
Néanmoins, le juge peut, même d'office, modérer ou augmenter la pénalité ainsi convenue si elle est manifestement excessive ou dérisoire.
Lorsque l'engagement a été exécuté en partie, la pénalité convenue peut être diminuée par le juge, même d'office, à proportion de l'intérêt que l'exécution partielle a procuré au créancier, sans préjudice de l'application de l'alinéa précédent.
Toute stipulation contraire aux deux alinéas précédents est réputée non écrite.
When the contract says that whoever fails to execute one of his or her commitments will pay a certain sum of money to the other party as damages, the other party cannot be granted a higher or lower sum.
However, the judge can, even on his or her own, decrease or increase the penalty so agreed if it is clearly too high or low.
When the commitment has been partially accomplished, the agreed penalty can be decreased by the judge, even on his or her own, in proportion of the interest that the other party received from partial execution, without prejudice of the previous paragraph.
Any clause contradicting any of the previous two paragraphs is void.
I highly recommend this commentary (if you can read French) for more information about the jurisprudence surrounding that article and the clause pénale concept in general. A rough summary:
- §1 establishes the general principle that the freely-contracting parties can put on price on a breach that can differ from the prejudice caused by a breach (whether actual, ex post, or reasonably-foreseeable, ex ante). The point of such penalty clauses (generally disallowed in common-law jurisdictions) is to incentivize performance of the contract.
- §2 does limit that principle for exceedingly unreasonable estimates. While the judge can modify the amount, it must be based on other motives than the ones rejected above; for instance the amount must be much higher/lower than typical for similar contracts;
- if the penalty is found to be too high or too low, it must not be changed beyond the actual (ex post) prejudice (assuming such prejudice can be reasonably quantified by the judge). That is, if the prejudice is $100 and the clause amount was "clearly too high" at $1000, the amount can be reduced to $500, $200 or $100, but not $50. Conversely, if the prejudice is $100 and the clause "clearly too low" at $10, the judge can bring it to $20, $50 or $100, but not $1000.
- additional damages can be claimed. For instance, suppose Bob promises to knit a sweater and give it to Alice next time she visits him, under penalty of $X. The first time Alice comes, Bob says he does not have the sweater, and tells her to come back later. Rinse and repeat: Alice repeatedly comes to Bob’s house asking for the sweater without getting it, before she eventually sues. At court, Alice can claim the $X amount, plus her travel costs to Bob’s house beyond the first visit (if she did those travels only in an attempt to get her sweater).
I will add that although §2 allows the judge to change the penalty amount even if no party asked for it, I would expect this to be a very rare occurrence.
Bob will likely argue that a $1 million penalty is "clearly too high" (manifestement excessive). If Bob shared a picture of Alice’s cat, I expect he would prevail, and the judge would operate a large reduction in the penalty. Other fact patterns may warrant otherwise, for instance
- if Bob is a millionaire and he shares an intimate picture of actress Alice, $1m could be a somewhat-reasonable amount and therefore would likely be sustained by the judge
- if Bob had undertaken to not set fire to Alice’s home under a penalty of $1, Alice (as unwise as she was to accept the contract in the first place) could successfully argue that $1 is manifestement dérisoire and she should recover more.