The Lincoln-based company took part in the programme, which it described as a "very worthwhile project", after installing a five-colour Heidelberg Speedmaster XL 75-5+L last year.
Achieving the colour standard was core to the company's latest press investment, which came specified with coater and Axis Control spectral measurement.
Ruddocks production manager Ady Potter said that despite necessary occasional press downtime, attaining the standard was a wholly positive move for the business.
He said: "We do believe this will open up new opportunities for us because many quotations demand specific details on quality and the certification will offer robust and credible evidence of our colour credentials.
"As well as reassuring our customers, this standard also allows us to save time and reduce waste in production. We can get to sellable copy much faster."
Ruddocks is the latest of 16 UK print businesses to achieve the ISO 12647-2 and its certification through Heidelberg is valid for the next two years.
"Build some flats on station car parks to pay for it."
"What an utter waste of taxpayers money."