Creates a LinkedIn campaign group — a 'Campaign' in the Campaign Manager UI. status: DRAFT | ACTIVE. If total_budget>0 is given, a total budget is assigned in the account's currency. RUN SCHEDULE: start_date / end_date ('YYYY-MM-DD'; end date runs to the end of that day, UTC). Empty start = now. With a total budget and no end_date LinkedIn's 90-day default end applies, so the budget is paced over 90 days — give end_date for event or short campaigns. LEAVE objective_type EMPTY unless you really want the whole group locked to one objective: an objective set at GROUP level constrains EVERY ad set inside it, so a group created with ENGAGEMENT can never host a Lead Generation or Website Visit ad set, and LinkedIn normally refuses to change it afterwards. Empty is the default and keeps the group open to every objective — set the objective on the individual campaign instead.

objective_type (LinkedIn's enum is SINGULAR — live-verified): WEBSITE_CONVERSION | WEBSITE_VISIT | WEBSITE_TRAFFIC | LEAD_GENERATION | BRAND_AWARENESS | ENGAGEMENT | VIDEO_VIEW | JOB_APPLICANT | CONVERSATION_STARTER | TALENT_LEAD | CREATIVE_ENGAGEMENT. Plural spellings (WEBSITE_CONVERSIONS / VIDEO_VIEWS / JOB_APPLICANTS) are auto-corrected. Objective CANNOT be changed after creation. If confirm=false, only a preview is returned; to apply, use confirm=true.