Fathom

Subsea capacity exchange · closed pilot

Trade subsea capacity without showing your hand.

Fathom is a blind marketplace for wavelengths, spectrum and fiber pairs. Sellers post offers, buyers post requests, and neither side ever sees the other’s book. Fathom matches them or runs an auction, and reveals who the counterparty is only once the deal is paid.

Request access How it works
Cross-section of a subsea cable route A cable leaves landing station A, runs down the continental shelf, across the abyssal plain and over a mid-ocean ridge, then climbs to landing station Z. Depths are illustrative.
fathom — a unit of depth, six feet; also, to understand something completely. Illustrative profile. Soundings in metres; vertical scale exaggerated.

The blind book

One order book, three views.

On an open board, posting a rate tells the market what you’ll take. On Fathom, only you and the operator can see your listing. Here is the same book as each party sees it.

A seller sees

Logged in as the owner of OF-3F7KQ

Offers

  • OF-3F7KQVirginia Beach (US) ⇄ Bilbao (ES) · 4×100G wavelength · lease 36 moask $19.50 /Gbps/mo
  • Another seller’s offer, hidden

Requests

  • A buyer’s request, hidden
  • A buyer’s request, hidden

Their own offers and asking rates, plus any proposal Fathom sends them — with the buyer shown only as Buyer B-4MZX.

Fathom sees

The operator holds the whole book

Offers

  • OF-3F7KQS-7KQ2 · Virginia Beach (US) ⇄ Bilbao (ES) · 4×100G · lease 36 moask $19.50 /Gbps/mo
  • OF-X2MWDS-M4TB · Marseille (FR) ⇄ Mumbai (IN) · 150 GHz spectrum · IRU 15 yr

Requests

  • RQ-4HTZMB-4MZX · US ⇄ ES, any station · 400G · lease 24–48 momax $24.00 /Gbps/mo
  • RQ-K2DVPB-9QRA · Singapore (SG) ⇄ Maruyama (JP) · 1 fiber pair · IRU 20–25 yr

Match OF-3F7KQ ↔ RQ-4HTZM · score 86
proposed $21.75 /Gbps/mo · TCV $313.2K

A buyer sees

Logged in as the owner of RQ-4HTZM

Requests

  • RQ-4HTZMUS ⇄ ES, any station · 400G wavelength · lease 24–48 momax $24.00 /Gbps/mo
  • Another buyer’s request, hidden

Offers

  • A seller’s offer, hidden
  • A seller’s offer, hidden

Their own requests and maximum rate, plus the proposal — with the seller shown only as Seller S-7KQ2.

Illustrative listings. The magenta figures are the ones the other side never sees: the seller’s ask and the buyer’s maximum. The proposed rate sits between them. Full visibility rules

Two ways to a deal

Fathom runs the market, so neither side has to reveal a price first.

Matching

Fathom scores every compatible offer–request pair on route fit, price, capacity, term and timing, then solves for the best set of matches across the whole book. Each side receives a proposal with firm terms and decides whether to accept.

  • The proposed rate is never below the seller’s ask and never above the buyer’s maximum.
  • Route flexibility is honoured: exact stations, same country, or same region.
  • A deal forms only when both sides accept before the proposal expires.
PROPOSAL · for RQ-4HTZMAwaiting your response

Virginia Beach (US) ⇄ Bilbao (ES)

Capacity
4 × 100G wavelength
Contract
Lease · 36 mo
Rate
$21.75 /Gbps/mo
TCV
$313.2K
Ready for service
2027-01-15
Counterparty
Seller S-7KQ2
AcceptDeclineExpires in 71 h · Illustrative

Auctions

When capacity is scarce or demand is crowded, Fathom invites the eligible counterparties to an auction instead. Forward auctions have buyers bid up on a seller’s offer; reverse auctions have sellers bid down to fill a buyer’s request.

  • English (open) with a minimum increment and a soft close, or sealed-bid first-price and second-price.
  • The seller’s reserve and the buyer’s ceiling stay hidden, and can’t be probed by bidding.
  • Bidders see the best rate, never who placed it.
REVERSE AUCTION · AU-7RWQELive · 04:12 left

Singapore (SG) ⇄ Maruyama (JP)

Lot
1 fiber pair · IRU 25 yr
Format
English, soft close 2 min
Best rate
$52,400 /pair/mo
Bids
7
Your best
$53,100 · not leading
Next valid bid
≤ $51,900
Place bidBuyer’s ceiling hidden · Illustrative

Who it’s for

Built for the people who buy and sell capacity for a living.

Sellers

Cable owners, consortium members, carriers holding IRUs, spectrum and wavelength resellers.

Place unsold or stranded capacity in front of qualified demand without publishing a rate card or tipping off competitors. Set a reserve nobody sees. Pay only when a deal closes.

Selling on Fathom

Buyers

Carriers, cloud and content providers, ISPs and enterprises building international networks.

Describe the route, capacity, term and date you need once. Keep your budget to yourself, let sellers compete for it, and pay no commission.

Buying on Fathom

Pricing

One fee, charged only on completed deals.

Fathom earns 3% of the total contract value of each deal, charged to the seller. Listing is free, proposals and auctions are free to take part in, and buyers pay no commission. Sellers see the fee and their net proceeds before they accept anything.

See a worked example

Where we are

A working pilot, stated plainly.

The exchange is built and running: listings, matching, auctions, deal desk messaging and payment. We’re now inviting a small number of sellers and buyers to use it on real routes.

We don’t publish traction figures or customer names; there aren’t any to publish yet. The landing-station and cable-system reference data in the app is illustrative, and Fathom holds no regulatory licences or approvals. What the pilot means for your data.

Have capacity to place, or a route to fill?

Tell us which routes and products matter to you. A person at Fathom reads every request and replies within two business days.

Request access