It is a substiute form used by the company to report the transactions. IRS allows reporting on such form. It does not affect your reporting requirements.
Let me know if you have any question.
Please note: This advice is provided with the understanding that all the relevant facts have been provided by you. Any change in facts might affect the advice given and hence may not be relied on in such cases. Nothing contained in this reply was intended or written to be used, can be used by any taxpayer, or may be relied upon or used by any taxpayer for the purposes of avoiding penalties that may be imposed on the taxpayer under the Internal Revenue Code of 1986, as amended.
Since they sold the shares, the gain on sale will be taxable.
You will report the sale on Sch D. You will also report your cost basis. The net gain from the sale will be taxable. The gain will be long term if the shares were held for more than a year.