Action: review if alternate sources are available, and keep these options at hand in case you need them.
Trading partners data
The case of trading partners data is very similar to the one of syndicated data, except that the data is usually not provided as a standalone service but as part of a broader relationship -- for example between a retailer and a manufacturer. Enforcing service level agreements can become tricky, if it puts at risk an otherwise profitable relationship.
Action: like you do for syndicated data, always have in mind alternate sources, if applicable.
Action: find multiple sources, and do not build your business on the assumption that open data feeds will remain available in the long run.
Harvesting data from web sites (screen scraping) or public APIs is common practice, but it is also the least secure source of data you can consider.
From the legal standpoint, this practice is often borderline since there is no licensing agreement that permits you to use the data harvested in such ways.
From the data availability standpoint, web sites change all the time, and your scraping routines will become obsolete in no time.
Action: stay away from data harvesting! And if data harvesting is your only option, be prepared to suffer outages, and to have to redevelop your routines all the time. And maybe get a lawyer....
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