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The type that defines the columns returned in the Item feed file.

Type that uses Item

ItemResponse

Call that uses Item

Fields

Field
Type
Description
itemId
The unique identifier of an item in eBay RESTful format. An example would be v1|1**********2|4**********2.
title
The seller created title of the item. This text is an escaped string when special characters are present, using the following rules:

  • Double quotes (") and backslashes (\) in the Title are escaped with a backslash (\) character
  • If there are any tabs (\t), double quotes ("), or backslashes (\) in the Title, the entire Title will be wrapped in double quotes.

For example

Before:

Misty Rainforest Modern Masters 2017 MTG Magic Fetch Land Free Ship W\Tracking

Marvel Legends HULK 8" Figure Avengers Age of Ultron Studios 6" Series

After:

"Misty Rainforest Modern Masters 2017 MTG Magic Fetch Land Free Ship W\\ Tracking"

"Marvel Legends HULK 8\" Figure Avengers Age of Ultron Studios 6\" Series"

imageUrl
The URL to the primary image of the item. This is the URL of the largest image available based on what the seller submitted.
category
The label of the category. For example: Toys & Hobbies|Action Figures|Comic Book Heroes
categoryId
The ID of the category of the item. For example: The ID for Toys & Hobbies|Action Figures|Comic Book Heroes is 158671.
buyingOptions
A comma separated list of the purchase options available for the item. Currently the only supported option is FIXED_PRICE.

Important! This field no longer returns values and is scheduled for deprecation.

sellerUsername
The seller's eBay user name.
sellerFeedbackPercentage
The percentage of the seller's total positive feedback.
sellerFeedbackScore
The feedback score of the seller. This value is based on the ratings from eBay members that bought items from this seller.
gtin
The unique Global Trade Item Number of the item as defined by https://www.gtin.info. This can be a UPC (Universal Product Code), EAN (European Article Number), or an ISBN (International Standard Book Number) value.
brand
The name brand of the item, such as Nike, Apple, etc.
mpn
The manufacturer part number, which is a number that is used in combination with brand to identify a product.
epid
The eBay product identifier of a product from the eBay product catalog. You can use this value in the Browse API search method to retrieve items for this product and in the Marketing API methods to retrieve 'also viewed' and 'also bought' products to encourage up-selling and cross-selling.
conditionId
The identifier of the condition of the item. For example, 1000 is the identifier for NEW. For a list of condition names and IDs, see Item Condition IDs and Names.

Code so that your app gracefully handles any future changes to this list.
condition
The text describing the condition of the item. For a list of condition names, see Item Condition IDs and Names.
priceValue
The price of the item, which can be a discounted price. If it is discounted, information about the discount is returned in the originalPriceValue, originalPriceCurrency, discountAmount, and discountPercentage columns.

Note: The price includes the value-added tax (VAT) for applicable jurisdictions when requested from supported marketplaces. In this case, users must pass the X-EBAY-C-MARKETPLACE-ID request header specifying the supported marketplace (such as EBAY_GB) to see the VAT-inclusive pricing. For more information on VAT, refer to VAT Obligations in the EU.
priceCurrency
The currency used for the price of the item. Generally, this is the currency used by the country of the eBay site offering the item.
primaryItemGroupId
The unique identifier for the item group that contains this item. An item group is an item that has various aspect differences, such as color, size, storage capacity, etc.
primaryItemGroupType
The item group type. Supported value: SELLER_DEFINED_VARIATIONS, indicates that the item group was created by the seller.

Code so that your app gracefully handles any future changes to this list.

Important! This field no longer returns values and is scheduled for deprecation.

itemEndDate
A timestamp indicating when the item's sale period will end based on its start date and duration. For Good 'Til Cancelled items, no value is returned in this column.

Format: UTC yyyy-MM-ddThh:mm:ss.sssZ
sellerItemRevision
An identifier generated/incremented when a seller revises the item. There are two types of item revisions:
  • Seller changes, such as changing the title
  • eBay system changes, such as changing the quantity when an item is purchased
This ID is changed only when the seller makes a change to the item.
itemLocationCountry
The country where the item is physically located.
localizedAspects
A semicolon separated list of the name/value pairs for the aspects of the item, which are Base64 encoded. The aspect label is separated by a pipe (|), the aspect name and value are separated by a colon (:) and the name/value pairs are separated by a semicolon (;).

Example without Label

   Encoded Format:
   encodedName:encodedValue;encodedName:encodedValue;encodedName:encodedValue

   Encoded Example (The delimiters are emphasized):
   U2l6ZQ==:WEw=;Q29sb3I=:UmVk;U2xlZXZlcw==:TG9uZw==

   Decoded:
   Size:XL;Color:Red;Sleeves:Long


Example with Label

   Encoded Format:
   encodedLabel|encodedName:encodedValue;encodedName:encodedValue;encodedLabel|

   Encoded Example (The delimiters are emphasized):
   UHJvZHVjdCBJZGVudGlmaWVycw==|R1RJTg==:MDE5MDE5ODA2NjYzMw==;QlJBTkQ=:QXBwbGU=;UHJvZHVjdCBLZXkgRmVhdHVyZXM=|TW9kZWw=:aVBob25lIDc=

   Decoded:
   Product Identifiers|GTIN:0190198066633;BRAND:Apple;Product Key Features|Model:iPhone 7

Note: The separators ( | : ; ) are not encoded. You must decode each label, name, and value separately. You cannot decode the entire string.

For more information, see Encoded Aspects in the Buying Integration Guide.

sellerTrustLevel
An enumeration value representing the eBay status of the seller.

Valid Values: TOP_RATED, ABOVE_STANDARD, or an empty value.

An empty value indicates a return of anything other than TOP_RATED or ABOVE_STANDARD.

Code so that your app gracefully handles any future changes to this list.
availability
An enumeration value representing the item's availability (possibility of being purchased).

Values:
  • AVAILABLE
  • TEMPORARILY_UNAVAILABLE
  • UNAVAILABLE
Code so that your app gracefully handles any future changes to this list.
imageAlteringProhibited
A boolean that indicates whether the images can be altered. If the value is true, you cannot modify the image.

Note: Due to image licensing agreements and other legal concerns, modification (including resizing) of some images is strictly prohibited. These images are for display as-is only.

estimatedAvailableQuantity
The estimated quantity of this item that are available for purchase. Because the quantity of an item can change several times within a second, it is very difficult to return the exact quantity. So instead of returning quantity, the estimated availability of the item is returned.

Note: If the seller of an item has the available threshold setting turned on, the value of this field will be null, and the availability of the item will instead be expressed through the availabilityThresholdType and availabilityThreshold fields.
availabilityThresholdType
This column has a value only when the seller sets their availability threshold preference. The value of this column will show MORE_THAN, which indicates that the seller has more than the available threshold preference in stock for this item. Because the quantity of an item can change several times within a second, it is very difficult to return the exact quantity.

Note: This field and the availabilityThreshold field will be returned as null if the actual quantity meets or drops below the threshold value, and then the buyer will want to look at the value in the estimatedAvailableQuantity field.
availabilityThreshold
This column has a value only when the seller sets their availability threshold preference. The value of this column will be "10", which is the threshold value.

Note: This field and the availabilityThresholdType field will be returned as null if the actual quantity meets or drops below the threshold value, and then the buyer will want to look at the value in the estimatedAvailableQuantity field.
returnsAccepted
Indicates whether the seller accepts returns for the item.
returnPeriodValue
The amount of days that the buyer has to return the item after the purchase date. For example, if this value is '30', the return period is 30 days.
returnPeriodUnit
An enumeration value that indicates the period of time being used to measure the duration, such as business days, months, or years.

TimeDurationUnitEnum is a common type shared by multiple eBay APIs and fields to express the time unit, but for return period duration, this value will always be DAY.
refundMethod
An enumeration value that indicates how a buyer is refunded when an item is returned.

Code so that your app gracefully handles any future changes to this list.

Important! This field no longer returns values and is scheduled for deprecation.

returnMethod
An enumeration value that indicates the alternative methods for a full refund when an item is returned. This column will have data if the seller offers the buyer an item replacement or exchange instead of a monetary refund.

Important! This field no longer returns values and is scheduled for deprecation.

returnShippingCostPayer
The party responsible for the return shipping costs when an item is returned.

Valid Values: BUYER or SELLER

Code so that your app gracefully handles any future changes to this list.
acceptedPaymentMethods
This field is returned empty. For a list of payment methods available for a marketplace, see eBay help pages or the actual View Item page.

Important! This field no longer returns values and is scheduled for deprecation.

deliveryOptions
A comma-separated list of available delivery options. This column lets you filter out items than cannot be shipped to the buyer.

Valid Values: SHIP_TO_HOME, SELLER_ARRANGED_LOCAL_PICKUP, IN_STORE_PICKUP, and PICKUP_DROP_OFF.

Code so that your app gracefully handles any future changes to this list.
shipToIncludedRegions
A pipe (|) separated alphabetical list of the geographic countries and regions where the seller will ship the item.

If a region is specified, you will need to subtract any countries and regions returned in the shipToExcludedRegions column to fully understand where the seller will ship.

The COUNTRY: list is separated from the REGION: list with a semicolon (;).

Format Example:
COUNTRY:US|BM|GL|MX|PM;REGION:AFRICA|ASIA|CENTRAL_AMERICA_AND_CARIBBEAN|EUROPE|MIDDLE_EAST|OCEANIA|SOUTH_AMERICA|SOUTHEAST_ASIA;

Country Values: The two-letter ISO 3166 standard code of the country.

Region Values: AFRICA, AMERICAS, ANTARCTIC, ARCTIC, ASIA, AUSTRALIA, CENTRAL_AMERICA_AND_CARIBBEAN, EUROPE, EURO_UNION, GREATER_CHINA, MIDDLE_EAST, NORTH_AMERICA, OCEANIA, REST_OF_ASIA, SOUTHEAST_ASIA, SOUTH_AMERICA, WORLDWIDE

Code so that your app gracefully handles any future changes to this list.
shipToExcludedRegions
A pipe (|) separated alphabetical list of the geographic countries and regions where the item cannot be shipped.

These countries and regions refine (restrict) the shipToIncludedRegions list. The COUNTRY: list is separated from the REGION: list with a semicolon (;).

Format Example:
COUNTRY:US|BM|GL|MX|PM;REGION:AFRICA|ASIA|CENTRAL_AMERICA_AND_CARIBBEAN|EUROPE|MIDDLE_EAST|OCEANIA|SOUTH_AMERICA|SOUTHEAST_ASIA;

Country Values: The two-letter ISO 3166 standard code of the country.

Region Values: AFRICA, AMERICAS, ANTARCTIC, ARCTIC, ASIA, AUSTRALIA, CENTRAL_AMERICA_AND_CARIBBEAN, EUROPE, EURO_UNION, GREATER_CHINA, MIDDLE_EAST, NORTH_AMERICA, OCEANIA, REST_OF_ASIA, SOUTHEAST_ASIA, SOUTH_AMERICA, WORLDWIDE

Code so that your app gracefully handles any future changes to this list.
inferredEpid
The ePID (eBay Product ID of a product in the eBay product catalog) for the item, which has been programmatically determined by eBay using the item's title, aspects, and other data.

If the seller actually provided an ePID at listing time for the item, the ePID value is returned in the epid column instead.
inferredGtin
The GTIN (Global Trade Item Number) of the product as defined by https://www.gtin.info, which as been programmatically determined by eBay. This can be a UPC (Universal Product Code), EAN (European Article Number), or an ISBN (International Standard Book Number) value.

If the seller provided a GTIN for the item, the seller's value is returned in the gtin column.
inferredBrand
The name brand for the item, such as Nike or Apple, which has been programmatically determined by eBay. To identify the product, this is always used along with MPN.

If the seller provided a brand for the item, the seller's value is returned in the brand column.
inferredMpn
The MPN (Manufacturer's Part Number) for the item, which has been programmatically determined by eBay. To identify the product, this is always used along with brand.

If the seller provided a MPN for the item, the seller's value is returned in the mpn column.
inferredLocalizedAspects
A semicolon separated list of the name/value pairs for the aspects of the item, which are Base64 encoded. These aspects have been programmatically determined by eBay. If the seller provided aspects for the item, the seller's values are returned in the localizedAspects column.

The aspect label is separated by a pipe (|), the aspect name and value are separated by a colon (:) and the name/value pairs are separated by a semicolon (;).

Example without Label

   Encoded Format:
   encodedName:encodedValue;encodedName:encodedValue;encodedName:encodedValue

   Encoded Example (The delimiters are emphasized):
   U2l6ZQ==:WEw=;Q29sb3I=:UmVk;U2xlZXZlcw==:TG9uZw==

   Decoded:
   Size:XL;Color:Red;Sleeves:Long


Example with Label

   Encoded Format:
   encodedLabel|encodedName:encodedValue;encodedName:encodedValue;encodedLabel|

   Encoded Example (The delimiters are emphasized):
   UHJvZHVjdCBJZGVudGlmaWVycw==|R1RJTg==:MDE5MDE5ODA2NjYzMw==;QlJBTkQ=:QXBwbGU=;UHJvZHVjdCBLZXkgRmVhdHVyZXM=|TW9kZWw=:aVBob25lIDc=

   Decoded:
   Product Identifiers|GTIN:0190198066633;BRAND:Apple;Product Key Features|Model:iPhone 7

Note: The separators ( | : ; ) are not encoded. You must decode each label, name, and value separately. You cannot decode the entire string.

For more information, see Encoded Aspects in the Buying Integration Guide.

additionalImageUrls
A pipe separated (|) list of URLs for the additional images of the item. These images are in addition to the primary image, which is returned in the imageUrl column. Note: This column can contain multiple values.
originalPriceValue
The original selling price of the item. This lets you surface a strikethrough price for the item.
originalPriceCurrency
The currency of the originalPriceValue of the item and the discountAmount.
discountAmount
The calculated amount of the discount (originalPriceValue - priceValue). For example, if originalPriceValue is 70 and priceValue is 56, this value would be 14.

Note: The currency shown in originalPriceCurrency is used for both discountAmount and originalPriceCurrency.

discountPercentage
The calculated discount percentage. For example, if originalPriceValue is 70 and discountAmount is 14, this value will be 20.
energyEfficiencyClass
Indicates the European energy efficiency rating (EEK) of the item. Data is returned in this column only if the seller specified the energy efficiency rating.

The rating is a set of energy efficiency classes from A to G, where 'A' is the most energy efficient and 'G' is the least efficient. This rating helps buyers choose between various models.

To retrieve the manufacturer's specifications for this item, when they are available, use the getItem method in the Browse API. The information is returned in the productFicheWebUrl field.
qualifiedPrograms
A pipe separated list of the qualified programs available for the item.

Valid Values:
  • EBAY_PLUS: Indicates an item is eligible for eBay Plus. eBay Plus is a premium account option for buyers, which provides benefits such as fast free domestic shipping and free returns on selected items.

    Note: eBay Plus is available only to buyers in Germany, Austria, and Australia marketplaces.
  • AUTHENTICITY_GUARANTEE: Indicates that the item is eligible for the eBay Authenticity Guarantee program. This program enables third-party authenticators to perform authentication verification inspections on items such as watches and sneakers.
  • FEATURED: Indicates that an item is eligible to be placed in a Focus Category. Focus Categories are specific categories dedicated to a certain type of product that allow a seller to better reach their target audience and increase their sales.
lotSize
The number of items in a lot. In other words, a lot size is the number of items that are being sold together.

A lot is a set of two or more items included in a single listing that must be purchased together in a single order line item. All the items in the lot are the same but there can be multiple items in a single lot, such as the package of batteries shown in the example below.

For example:

Item Lot Definition Lot Size
A package of 24 AA batteries A box of 10 packages 10
A P235/75-15 Goodyear tire 4 tires 4
Fashion Jewelry Rings Package of 100 assorted rings 100


Note: Lots are not supported in all categories.
lengthUnitOfMeasure
The unit of measurement used for the package dimensions, such as INCH, FEET, CENTIMETER, or METER.

Code so that your app gracefully handles any future changes to this list.

Important! This field no longer returns values and is scheduled for deprecation.

packageWidth
The width of the shipping package that contains the item.

Important! This field no longer returns values and is scheduled for deprecation.

packageHeight
The height of the shipping package that contains the item.

Important! This field no longer returns values and is scheduled for deprecation.

packageLength
The length of the shipping package that contains the item.

Important! This field no longer returns values and is scheduled for deprecation.

weightUnitOfMeasure
The unit of measurement used for the package weight, such as POUND, KILOGRAM, OUNCE, or GRAM.

Code so that your app gracefully handles any future changes to this list.

Important! This field no longer returns values and is scheduled for deprecation.

packageWeight
The weight of the package that contains the item.

Important! This field no longer returns values and is scheduled for deprecation.

shippingCarrierCode
The name of the shipping provider, such as FedEx, or USPS.

Important! This field no longer returns values and is scheduled for deprecation.

shippingServiceCode
The type of shipping service. For example, USPS First Class.

Important! This field no longer returns values and is scheduled for deprecation.

shippingType
The type of a shipping option, such as EXPEDITED, ONE_DAY, STANDARD, ECONOMY, PICKUP, etc.
shippingCost
The final shipping cost for all the items after all discounts are applied.

Note: The price includes the value-added tax (VAT) for applicable jurisdictions when requested from supported marketplaces. In this case, users must pass the X-EBAY-C-MARKETPLACE-ID request header specifying the supported marketplace (such as EBAY_GB) to see the VAT-inclusive pricing. For more information on VAT, refer to VAT Obligations in the EU.
shippingCostType
Indicates the class of the shipping cost.

Valid Values: FIXED or CALCULATED.
additionalShippingCostPerUnit
Any per item additional shipping costs for a multi-item purchase. For example, let's say the shipping cost for a power cord is $3. But for an additional cord, the shipping cost is only $1. So if you bought 3 cords, the shippingCost would be $3 and this value would be $2 ($1 for each additional item).

Important! This field no longer returns values and is scheduled for deprecation.

quantityUsedForEstimate
The number of items used when calculating the estimation information.

Important! This field no longer returns values and is scheduled for deprecation.

unitPrice
This is the price per unit for the item. Some European countries require listings for certain types of products to include the price per unit so buyers can accurately compare prices.

For example:

"unitPricingMeasure": "100g",
"unitPrice": {
  "value": "7.99",
  "currency": "GBP"
unitPricingMeasure
The designation, such as size, weight, volume, count, etc., that was used to specify the quantity of the item. This helps buyers compare prices.

For example, the following tells the buyer that the item is 7.99 per 100 grams.

"unitPricingMeasure": "100g",
"unitPrice": {
  "value": "7.99",
  "currency": "GBP"
legacyItemId
The unique identifier of the eBay listing that contains the item. This is the traditional/legacy ID that is often seen in the URL of the listing View Item page.
alerts
A pipe-separated list of alerts available for the item.

For example, if the DELAYED_DELIVERY alert was returned for an item, it would indicate a delay in shipping by the seller.
sellerAccountType
A string value that specifies whether the seller is a business or an individual. This is determined when the seller registers with eBay. If the seller registers for a business account, the value returned in this field will be BUSINESS. If the seller registers for a private account, the value returned in this field will be INDIVIDUAL.

Note: This designation is required by the tax laws in some countries.

This field is returned only on the following sites: EBAY_AT, EBAY_BE, EBAY_CH, EBAY_DE, EBAY_ES, EBAY_FR, EBAY_GB, EBAY_IE, EBAY_IT, and EBAY_PL.

Code so that your app gracefully handles any future changes to this list.

Valid Values: BUSINESS or INDIVIDUAL
tyreLabelImageUrl
The URL to the image that shows the information on the tyre label.
priorityListingPayload
EPN (eBay Partner Network) publishers append this value to their affiliate tracking URL when using an EPN tracking link to track changes that occur to Priority Listing items.

Example:amdata=enc%3AAQAFAAAAkB1DmsmXf%2BqZ%2BCEMGdebW6oR75GCMdBmc4MCQ%2FCEPqgKHbT0jdWhPwfY5LdUs6HTaP0eBlwKE7Smy2eDslewF7l3xjwWxjqwzNAnsYgxn2PiGkTKbiQSQytFUiymdtANpk1qOnBOoMGMK%2BWsji7jYlvySSs9o9s24TxD6RqWZpNrltzOU7mfnv3H40SZ3YESzg%3D%3D

See Creating an EPN Tracking Link for information on EPN tracking links.
itemCreationDate
A timestamp indicating when the item was created.

Format: UTC yyyy-MM-ddThh:mm:ss.sssZ
itemWebUrl
The URL of the View Item page of the item.

For example:

Single SKU:
https://www.ebay.de/itm/2********0

MSKU:
https://www.ebay.com/itm/2********9?var=5********2
defaultImageUrl
URL to the gallery or default image of the item. The other images of the item are returned in the additionalImageUrls field.

For example

https://i.ebayimg.com/00/s/M********w/z/W********p/$_1.JPG?set_id=8********F
itemAffiliateWebUrl
The URL of the View Item page of the item, with the affiliate tracking ID appended to it.

For example

https://www.ebay.de/itm/2********0?mkevt=1&mkcid=1&mkrid=707-53477-19255-0&campid=CAMPAIGNID&toolid=2***6&customid=CUSTOMID
ageGroup
The age group that the product is recommended for.

Valid values: newborn, infant, toddler, kids, adult.
color
The color of the item.
pattern
Text describing the pattern used on the item. For example, paisley.

Note: All the item aspects, including this aspect, are returned in the localizedAspects container.
size
The size of the item.
gender
In cases where items could vary by gender, this specifies for which gender the product is intended. Possible values include male, female, and unisex.
material
The material that the item is made of.
totalUnits
For an item that is priced by the unit, the total number of units that are on offer. For example, if the item is priced by the meter and 50 cm is on offer, the totalUnits would be 0.5 m.
ecoParticipationFeeValue
The amount of the Eco Participation Fee, a fee paid toward the eventual disposal of the purchased item.
ecoParticipationFeeCurrency
The currency in which the Eco Participation Fee for the item is paid.
takeBackPolicyLabel
The seller-defined label of the TAKE_BACK custom policy for the item. A TAKE_BACK policy describes the seller's regulatory responsibility to take back a purchased item for disposal when the buyer purchases a new one.
takeBackPolicyDescription
The seller-defined description of the TAKE_BACK custom policy for the item.
hazmatSignalWordId
The ID of the signal word for the hazardous material.
hazmatSignalWord
The localized signal word for the hazardous material, such as 'Danger'.
hazmatStatementIds
The IDs of hazardous material statements, separated by the pipe symbol. For example:

H200|H221
hazmatStatementDescriptions
The Base64 encoded descriptions of hazardous material statements, separated by the pipe symbol. For example:

encoded(Unstable explosives)|encoded(Flammable gas)
hazmatPictogramIds
The IDs of hazardous material pictograms, separated by the pipe symbol. For example:

SGH01|SGH02
hazmatPictogramDescriptions
The Base64 encoded descriptions of hazardous material pictograms, separated by the pipe symbol. For example:

encoded(exploding bomb)|encoded(flame)
hazmatPictogramImageUrls
The image URLs of hazardous material pictograms, separated by the pipe symbol. For example:

https://img1|https://img2
hazmatAdditionalInformation
Base64 encoded additional information about the hazardous material.
repairScore
A score that describes how easy it is to repair the product. Score values range from 0.1 (hardest to repair) to 10.0 (easiest), always including a single decimal place.
conditionDescriptors
Note: Condition descriptors are currently only available for the following trading card categories:
  • Non-Sport Trading Card Singles
  • CCG Individual Cards
  • Sports Trading Card Singles

This field contains a list of the name/value pairs for the condition descriptors of the item, which are Base64 encoded. The descriptors are separated as follows:
  • Name and value pairs are separated by a colon :
    Name:Value

    Base64 encoding the above pair yields TmFtZQ==:VmFsdWU=
  • Multiple descriptors are separated by a semicolon ;
    Name1:Value1;Name2:Value2

    Base64 encoding the above multiple descriptors yields TmFtZTE=:VmFsdWUx;TmFtZTI=:VmFsdWUy
  • Multiple values are separated by a pipe |
    Name1:Value1|Value2|Value3;Name2:Value1|Value2|Value3

    Base64 encoding the above multiple values (for multiple descriptors) yields TmFtZTE=:VmFsdWUx|VmFsdWUy|VmFsdWUz;TmFtZTI=:VmFsdWUx|VmFsdWUy|VmFsdWUz
Note: The separators ( : ; | ) are not encoded. You must decode each name, and value or values separately. You cannot decode the entire string.
The name and value are numeric IDs that map to the name and value, respectively, of a condition descriptor. A condition descriptor name-value pair provides more information about an item's condition in a structured way. Descriptors are name-value attributes that can be either from a closed set or open text. For more information on the numeric IDs and their text equivalents, use the getItemConditionPolicies method of the Metadata API.
sellerUserId
The unique identifier of an eBay user across all eBay sites. This value does not change, even when a user changes their username.