Disclosure: Brun is our product. Acrobat is the standard PDF tool for good reason, and we say below where Adobe is the better pick.
What Adobe Acrobat and Acrobat Sign are built for
Acrobat is the PDF editor most firms already own. It creates, edits, combines and redacts PDFs, and its business plans include sending documents for e-signature through Acrobat Sign, with no cap on signature requests on the teams plans. Larger organisations can buy Acrobat Sign Solutions for workflow automation and enterprise controls. If your work is preparing documents, Acrobat is hard to beat.
What Brun is built for
Brun is not a PDF editor. It is a client portal for small law firms: you send the finished PDF for signature from the same private page where the client sends you files, reads your progress updates and talks to your team. Brun doesn’t compete with Acrobat on editing. It competes on what happens around the signature:
- It proves receipt. When a client sends you their documents, they see Delivered and then Opened by the person at your firm who opened them. Adobe gets the agreement signed; Brun also shows the client their documents arrived.
- It keeps the exchange in one place. Signatures, files in both directions, updates and messages per matter, instead of signing in one tool and everything else in email.
- Nobody at the vendor can open it. Documents are encrypted in the browser. Brun stores ciphertext and has no AI that reads your agreements.
Side by side
| Adobe Acrobat / Acrobat Sign | Brun | |
|---|---|---|
| Primary job | Create and edit PDFs; send for signature | The client exchange: intake, files, signatures, updates, messages |
| PDF editing, OCR, redaction | Yes | No |
| Signer needs an account | No | No |
| Encryption | TLS in transit, AES-256 at rest; Adobe manages keys by default | End-to-end: encrypted in the browser, Brun never holds the key |
| Customer-managed keys | In the enterprise Acrobat Sign Solutions tier | Always |
| AI that reads your documents | AI Assistant (Adobe says content isn't used to train models) | None |
| Uses existing PDF form fields | Yes | Yes: detects text, checkbox and signature fields |
| Firm countersignature | Yes, as an additional signer | Yes, the document returns to you after the client signs |
| Several signers in order | Yes | No: one client signer plus your countersignature |
| Client sends you files | Not a file-exchange tool | Any file up to 2 GB, with Delivered / Opened receipts |
| Progress updates and messaging | No | Yes, encrypted, per matter |
Which one to pick
Adobe is the better pick when
- You need to edit, combine, redact or OCR PDFs.
- Documents need several signers in sequence.
- You want signing inside an enterprise document workflow.
Brun is the better pick when
- The document is finished and the hard part is the client.
- You collect files, photos and video from clients and need proof they arrived.
- No vendor’s systems should be able to read the documents.
What Brun doesn’t do
Brun doesn’t edit PDFs, route to several signers, or run templates or bulk sends. It has no integrations or API and no AI. It is for small firms, not an enterprise document platform.
Can you use both?
Yes, and that is the usual setup: prepare the document in Acrobat, export the final PDF, and send it through the client’s Brun portal. The client signs on their phone, and the signed copy with its certificate of completion stays on the portal for both of you.
Related: Brun vs DocuSign and how to get clients to sign documents online.
Sources (checked November 2, 2026): adobe.com/acrobat/business/sign.html, adobe.com/acrobat/online/request-signature.html, adobe.com/acrobat/online/ai-chat-pdf.html, Adobe Acrobat Sign Security Overview (June 2026). Adobe and Acrobat are trademarks of Adobe; Brun is not affiliated with Adobe.