Indicates the priority of a LineItem, determined by the way in which impressions are reserved to be served for it.

| Enums ||
|---|---|
| `LINE_ITEM_TYPE_UNSPECIFIED` | Not specified value. |
| `SPONSORSHIP` | The type of LineItem for which a percentage of all the impressions that are being sold are reserved. |
| `STANDARD` | The type of LineItem for which a fixed quantity of impressions or clicks are reserved. |
| `NETWORK` | The type of LineItem most commonly used to fill a site's unsold inventory if not contractually obligated to deliver a requested number of impressions. Uses daily percentage of unsold impressions or clicks. |
| `BULK` | The type of LineItem for which a fixed quantity of impressions or clicks will be delivered at a priority lower than the STANDARD type. |
| `PRICE_PRIORITY` | The type of LineItem most commonly used to fill a site's unsold inventory if not contractually obligated to deliver a requested number of impressions. Uses fixed quantity percentage of unsold impressions or clicks. |
| `HOUSE` | The type of LineItem typically used for ads that promote products and services chosen by the publisher. |
| `CLICK_TRACKING` | The type of LineItem used for ads that track ads being served externally of Ad Manager. |
| `ADSENSE` | Targets the LineItem to specific inventory available to AdSense buyers. |
| `AD_EXCHANGE` | Targets the LineItem to specific inventory available to Authorized Buyers and the Open Auction. |
| `BUMPER` | Represents a non-monetizable video LineItem that targets one or more bumper positions, which are short house video messages used by publishers to separate content from ad breaks. |
| `PREFERRED_DEAL` | The type of LineItem for which there are no impressions reserved, and will serve for a second price bid. |
| `AUDIENCE_EXTENSION` | The type of LineItem used for configuring audience extension campaigns. |