Semacode is a private company and also this company’s trade name for machine-readable ISO/IEC 16022 Data Matrix symbols which encode internet Uniform Resource Locators (URLs). It is primarily aimed at being used with cellular phones which have built-in cameras. The Data Matrix specification is given by the ISO/IEC 16022 standard.
Source: Wikipedia <Link>
That’s the reason for that two-dimensional barcode which looks like a dense crossword puzzle found in websites.
High Tech DoCoMo ad that features Semacode <link>
Ajinomoto Stadium (Beautiful Girls) <link>