history of cook county recorder of deeds karen yarbrough

A decades old paper record certification stamper, to demonstrate how far technology has come

As her final innovation as Recorder of Deeds, Karen A. Yarbrough is announcing that the Cook County Recorder of Deeds will soon offer paperless Certified Digital Files, in addition to certified paper copies.

This expansion of service, made possible with the help of Onyx Electronics, will allow customers to obtain a certified copy of an existing land record much faster and easier than visiting our office, or waiting for a paper copy to be mailed. While certified computer files are not new, CCRD may be the first county recorder in the nation to offer this service along with a secondary certification using a public blockchain database.


What is a Certified Digital File?

Until now, if a customer needed a Certified Copy of a record, such as their deed, they had to obtain a paper (hard) copy. A staff member of CCRD would print out the document from our database, then use an embosser, or stamper, to physically mark the paper. This is generally placed on only one page of the document.

A Certified Digital File is a PDF document that has been inspected, verified and created by a CCRD Employee, with each page watermarked with the unique “digital fingerprint” of that file in CCRD’s database. CCRD is using the PDF/A (archival) standard, specifically PDF/A 1-b. which is a long-term file storage format compliant with ISO 19005-1:2005 Standards. A cover page that is also watermarked is placed in the PDF as a secondary means of verification if the PDF/A is printed.

The customer can use CCRD/Onyx’s online tool to verify the authenticity of the PDF. If the customer emails the PDF to a 3rd party such as an attorney, Judge or a Court Clerk, that person can confirm that the file is an authentic copy of a CCRD record by using the public Verify tool.

Paperless record certification is more secure and accurate than paper certification. Why? For example, a person committing fraud could buy a certified paper copy, then cleverly forge or change part of the text of the document in a way that may not be detected by the human eye. If a fraudster tries to change even one pixel or character in a Certified Digital File, the online Verification Tool will detect this change and tell the inspector that the document is no longer a true copy of a CCRD record.


What is a SHA 256 hash, and what is blockchain?

Every piece of data or information, including computer files, has a unique “digital fingerprint” or “hash,” if a standard hashing algorithm is used. In a database of 50 million files, no two files will have the same hash value. This technology is used to verify large quantities of data. For example, if you are moving 50 million photos from one database to another, you can compute the hash value of all files together, than compare your destination storage drive that value to make sure every pixel of every file was transferred, rather than having to verify each record individually.

A blockchain is a distributed and public immutable ledger. By using hash technology, one can certify to a public database that a certain file existed at a certain time. If you write a poem and save that poem as a PDF, then embed that PDF’s hash value in the bitcoin blockchain, you can prove that the poem existed at that time. In the future if someone copies and publishes your poem, you can use the record from the immutable ledger to prove that it existed before they published it.

Because hash values are made from “one-way” cryptographic functions, the fingerprint of private data can be published publicly without fear that someone can reverse the public hash and decipher the private information used to create it. For example, the author of this post can give you the hash of his home address (AB8538913C8294BCAA1A3E5B3F5EBED64761AF33DFC6766CDECBD0546F620A85) without fear that anyone can reverse it and stop by for a visit.

In 2016, CCRD made international news by announcing that it endorsed blockchain technology in general, and launched the first-ever county-level proof of concept in North America. CCRD’s Final Blockchain Report was published in 2017, and can be accessed by clicking here.

CCRD/Onyx is using the SHA 256 standard developed by the National Security Agency.


What is being certified?

To understand CCRD’s process, it is first important to understand exactly what CCRD certifies. When a customer receives a certified copy, they are receiving proof that the record in their hand is the same one that was submitted for recordation at the time and date printed in the upper right corner of the document. CCRD does not certify that the transaction described in the document actually happened, or happened as described.

For CCRD’s Certified Digital Files, two things are being certified. First, the unique hash value of the underlying database file is watermarked onto the PDF, along with the date of certification and number of pages. Second, when the Certified Digital File is created by an employee, the hash value of that PDF (which is different than the hash watermarked on the document), is embedded into the bitcoin blockchain at the time of creation and provided to the customer as certification that the document was created by CCRD.

These two certifications, working together, allow provably secure paperless records certification.


How can Certified Digital Files be authenticated by the public?

Anyone in doubt about the authenticity of the PDF has two ways to verify it. First, they can search any public bitcoin blockchain explorer for the blockchain Transaction ID provided to them in the delivery email, to ensure that it is not fraudulent. Second, they can visit CCrecorder.org/verify, then simply upload the PDF into the public verification tool.

If the file is authentic and unchanged, the customer will receive an immediate confirmation that the file is authentic. If the file is fake or edited in any way, the online verification tool will not provide confirmation that the file is valid. Both methods of verification are not required. A message of VERIFIED tells you that the PDF is a true and accurate copy of our record, AND that it was created by a CCRD employee.


How to order a Certified Digital File


Visit our Data Portal at CCRecorder.org. Find the document you are looking for by searching for it by Document Number or by searching the PIN or Address. Click the red button called CERTIFIED PDF to begin the process to pay for your Certified Copy (price is the same as a normal Certified Copy; there is no extra charge for a Digital Certification). Once you have paid, (you will need to create an Account first) your order will be sent to a CCRD employee and fulfilled as soon as possible. Please note, if you place your order near the end of the day or at night or on a weekend, it will be processed the next business day.

Once processed, you will receive an email with the PDF/A attached, and the email will contain your receipt of blockchain certification.



This new service is in testing phase, and CCRD is unable to guarantee that 3rd Parties will accept this paperless record instead of paper. You should check with the requestor before ordering.  This service is intended for short to medium-term storage goals. CCRD does not guarantee the long-term viability of the technical standards utilized, including PDF/A or the Secure Hashing Algorithm 256. CCRD reserves the right to change the archival or file standards used, and/or the hashing algorithm or method.