Since the mandatory move to the French INPI Guichet Unique in 2023, all company formalities (formation, amendment, cessation, accounts filing, trademark filing) are done online at procedures.inpi.fr. At the end of each formality, the portal generates a PDF summary that you must sign electronically before uploading it back for validation.
The operation seems simple, but it often blocks: signature rejected, FranceConnect+ down, inadequate signature level. Here's the complete procedure that works the first time.
Before starting: what you need
- The PDF summary downloaded from the Guichet Unique. Don't open it in Adobe Reader, don't print it, don't re-save it — that invalidates the future signature.
- A valid official ID: national ID card, passport, or residence permit. Driving licences and family record books are not accepted.
- A smartphone with camera and SMS access for PVID identity verification.
- A valid email to receive the signed PDF.
- 5 minutes of available time.
Step 1 — Identify the right signature level
The European eIDAS regulation defines 3 levels of electronic signature:
- Simple signature: an email, a click, a tickbox. No strong identity check. Rejected by INPI.
- Advanced signature: identity verified but without a certificate from a qualified provider. Rejected by INPI for most formalities.
- Qualified signature: identity verified + certificate issued by a Qualified Trust Service Provider listed on the EU Trust List. The only level accepted by the Guichet Unique for sensitive formalities.
For amendment, cessation, accounts filing, trademark or patent filing, it's mandatorily the qualified level.
Step 2 — Download the PDF summary
On procedures.inpi.fr, at the end of your formality, you arrive at the "Summary signature" step. The portal offers to download the recap PDF.
Best practices:
- Click "Download" and save the file on your computer.
- Don't open it in Adobe Reader and re-save it (this modifies the PDF and invalidates the future signature).
- Don't print and re-scan: electronic signature requires an original PDF, not an image.
- Verify the file is complete (no blank pages, no "draft" mention).
Step 3 — Choose a qualified signature route
Option A: FranceConnect+ via certified La Poste Digital Identity
The "official" route offered by the Guichet Unique. Click "Sign with FranceConnect+" and you're redirected to the La Poste app to validate.
Conditions: have a La Poste Digital Identity at certified level (prior post office visit). If you don't have it, expect 2 to 5 working days to get it.
Risk: the service regularly fails. Blank page, orange banner, reload loop. See FranceConnect+ doesn't work on INPI.
Option B: specialised qualified provider (the fastest)
You upload the PDF summary to SignerSynthèse.fr or another qualified provider listed on the EU Trust List. The provider verifies your identity via PVID (ID photo + selfie + SMS), applies the qualified signature, and emails you the signed PDF.
Time: 2 to 5 minutes. Cost: €29 ex. VAT at SignerSynthèse.fr (one-time payment). No travel.
Option C: qualified certificate on USB token / smart card
Reserved for professionals who sign often. Time: 1 to 4 weeks. Cost: €100 to €250 ex. VAT for a 1- to 3-year certificate. See our pricing comparison.
No time for FranceConnect+?
eIDAS qualified electronic signature on your INPI summary in 2 minutes. €29 ex. VAT, delivered by email, 100% accepted by the Guichet Unique.
Sign my summary →Step 4 — The signature journey (option B, the simplest)
Here's what the journey looks like at SignerSynthèse.fr — representative of what modern qualified providers offer:
- PDF upload: drag your summary on the home page or click to browse. The file is encrypted and temporarily stored.
- Signer identification: first name, last name, email, phone (E.164 format). This information is cryptographically embedded in the signature certificate.
- Payment: €29 ex. VAT by card (Visa, Mastercard, Amex, Apple Pay, Google Pay). Stripe handles the transaction.
- PVID identity verification: redirect to the provider's verification app (Universign). Front/back photo of your ID, face-camera selfie, SMS confirmation code.
- Qualified signature applied: the provider automatically applies the eIDAS qualified signature and redirects you.
- Receive the signed PDF: the PDF arrives by email with an embedded certificate (LTV signature — Long Term Validation).
Total duration: 2 to 5 minutes.
Step 5 — Upload the signed PDF back to the Guichet Unique
Go back to procedures.inpi.fr, find your formality (status "Awaiting signature"), and upload the signed PDF at the dedicated location.
The Guichet Unique automatically verifies:
- That the PDF matches the one it generated (cryptographic integrity).
- That the signature is at qualified eIDAS level.
- That the signature provider is listed on the EU Trust List.
If everything passes, your formality moves to "Validated" status instantly. Otherwise, you receive a precise error message (see INPI summary rejected: 7 possible causes).
Pre-upload checks
1. The PDF was not modified
Don't reopen it in Adobe Reader between signing and uploading. Any modification (even an open-and-close without modification) can alter metadata and invalidate the signature.
2. The right PDF is uploaded
Verify you upload the signed PDF, not the original. The filename usually changes after signing (a _signed suffix or similar is added).
3. You are the right signer
For an SARL/SAS, the director or chairman in office signs. For a company formation, the founder. A signature by an unauthorised third party will be rejected.
4. All pages are signed
The qualified signature applies to the entire document, but some registries visually check the presence of the signature banner at the foot of each page. Our provider adds this banner automatically.
FAQ: signing a document on INPI
How long does it take to sign?
2 to 5 minutes via a specialised qualified provider. 5 to 30 minutes via FranceConnect+ if everything works. Several days if you must first obtain a certified La Poste Digital Identity.
What's the cost?
FranceConnect+ with La Poste Digital Identity: technically free (but physical visit required). Pay-as-you-go qualified provider: €29 ex. VAT at SignerSynthèse.fr. See INPI signature pricing comparison.
Does the qualified signature have the same legal value as a handwritten signature?
Yes. EU Regulation 910/2014 article 25 states that the qualified signature has legal value equivalent to a handwritten signature in all EU Member States.
Can I sign for someone else?
No. The qualified signature is strictly personal. The signer must be physically present for PVID identity verification. A signature by proxy requires a specific procedure with a qualified provider.
What if the signature is rejected?
See our INPI summary rejected guide. Possible causes: insufficient signature level, PDF modified after signing, non-qualified provider, wrong signer.
Conclusion
Signing an INPI document on the Guichet Unique boils down to 3 key actions:
- Download the PDF summary without modifying it.
- Sign it with an eIDAS qualified signature via FranceConnect+ or a specialised provider.
- Upload the signed PDF back to the Guichet Unique.
If you're in a hurry or if FranceConnect+ doesn't work, a pay-as-you-go qualified provider saves you several days for €29 ex. VAT.