One misdirected drawing set can hand a competitor your bid — and your IP.
Revision rounds move fast, and autocomplete doesn't care that "Client Engineering" at the firm across town isn't who this drawing set is for.
It's not carelessness. It's near-identical contact names across competing bidders.
Firms bidding on the same project often deal with contacts who have nearly identical titles — "Project Engineer," "Client Rep" — at companies with similar-sounding names. Mid-revision, with three redlines open across two bids, autocomplete fills in whichever contact it saw most recently. The proprietary drawing set or spec sheet for one client goes to the engineer at a competing firm instead.
That's not a document you get back. Once a competitor has your drawings, they've seen your approach, your specs, and often your pricing structure implied by the scope of work — enough to undercut your bid or replicate your design choices without the R&D cost you paid. On a public project, it can also trigger a procurement integrity concern if the wrong party gained an information advantage before award.
Beyond the immediate deal, proprietary designs are IP your firm built over years. A single email can put that IP in a competitor's hands permanently, with no way to un-ring that bell.
What the sender sees in Outlook — before the email leaves the outbox.
File-sharing platforms protect the file. They don't protect the notification email.
Many firms route drawings through a project-management or file-sharing platform (Procore, PlanGrid, or similar) with access controls — genuinely effective for the files themselves. The gap is the notification email, the quick "here's the redline" send, or the cover note that goes out through regular Outlook because the platform's workflow is slower than the deadline allows.
The other standard practice is "double-check before you send during revision rounds." It's sound advice that competes directly with the deadline pressure of a live bid — the moment staff are moving fastest through revisions is exactly when the check gets skipped.
A guardrail on the Outbox, not just the file-share platform.
Sendasta checks the recipient list — To, Cc, and Bcc — against rules your firm sets, at the exact moment someone clicks Send in Outlook. It never opens the drawing set or attachment, so your IP stays exactly as protected as it was before the check ran.
- Blocked domains — flag a competing firm's domain outright. If it shows up as a recipient, the send is paused before anything goes out.
- No-combine pairs — flag two client or bidder domains that should never appear on the same thread, useful when your firm is bidding against itself indirectly through different teams.
- Trusted pairs — mark legitimate multi-party combinations (a joint venture partner, a subcontractor) as trusted once, so you're not interrupted on routine sends.
For firm-wide protection across every active bid, an admin pushes shared blocked-domain policy to every engineer's Outlook via the Microsoft 365 Admin Center. Individuals can layer their own project-specific rules on top for the bidders and clients on their current work.
Frequently asked
Does Sendasta read the CAD files or specs attached to the email?
No. Sendasta only checks the addresses in the To, Cc, and Bcc fields against your firm's rules — it never opens the drawing set, the spec sheet, or any attachment. The check happens locally in Outlook the moment someone clicks Send, and nothing about the file's content is ever transmitted anywhere.
Can it stop drawings from going to a competing bidder by accident?
Yes — flag a competing bidder's or competing firm's domain as blocked, and any email addressed to it gets paused before it sends, regardless of how the address ended up in the field. You can also flag "no-combine" pairs for two clients whose projects should never cross on the same thread.
Will this slow down revision rounds during a tight project schedule?
No — the check adds under a second and only interrupts a send when it matches a rule. Every other revision send — the vast majority — goes through exactly as fast as it does today.
Can we set this up per-project instead of firm-wide?
Individual engineers can set their own rules for the clients and projects they're personally working on. For baseline protection across every active project, an admin can also push shared blocked-domain policy to the whole firm via the Microsoft 365 Admin Center, and individuals layer their own project-specific rules on top.
Protect the bid before the send, not after.
Get started free for personal use, or reach out and we'll walk you through setting up firm-wide policy for your team.