开展联系人定向时，您最多可以上传 300,000 个联系人。

The statement is correct. LinkedIn allows advertisers to upload up to 300,000 contacts for Matched Audiences targeting. This feature enables businesses to target specific individuals from their customer lists, CRM data, or email lists, enhancing the precision of their advertising campaigns. Uploading a smaller number of contacts is also acceptable, but 300,000 is the upper limit for a single upload.