Dear Krishna
you need to differentiate "search" and the "maintenance".; in most case the "search" is the most expensive step; e.g. google and other tools are "helping" sometimes to collect some data; but normally this kind of data need to be searched for by different methods
Maintenance. different kind of aspect: I am not "100 %" sure but in former times TechniData (more specific a company related to TechniData) maintained such data "on behalf" of company XY in the SAP system. I am not 100% if the SAP services (which exists according to my knowledge) covers this "maintenance" (and may be as well the "search part);
But in > 80% of the cases REAL_SUB data is maintained by the company using SAP; how they collect the data is organized inmost cases comapny specific
E,g. if you look for the REACH aspect the story is here "special". EU companeids are "forced" by regulation to share the data (including physical chemical data); if the data doe snot exist; of they can not find any data provider or agent who can provide the data: you have no other options as to make the "measurement" to get e.g,the density
And here comes "IUCLID" in place; if your are one "registrant" you need to share the data with otthers using IUCLID; but then you can as well use the data form other companies (but as always: you have tp pay for this).
C.B.