Stamp or notarize data into a public witnessed transparency log. Proves timing, not truth.
Free
One server, in finance & commerce. Stamp or notarize data into a public witnessed transparency log. Proves timing, not truth.
Finance & Commerce
Stamp or notarize data into a public witnessed transparency log. Proves timing, not truth.
The rest either hold an API key issued by the publisher or ask for nothing.
Listed without a verification tick. Read the listing before installing.