Salesforce duplicates

[Amber_Hobson]

As our company is growing, we are acquiring new companies. When we do this, we are adding their databases to our Salesforce database. By doing this, it always adds a lot of duplicates to Marketo. I know in theory we should be adding our lists to Marketo first to get rid of the duplicates. But we can't do that with the way our company is structured. 

If we get a de-duplication tool in Salesforce to get rid of duplicates in that system, will it push back to Marketo and merge those records together? Or do I have to do the de-duplication in Marketo and then push it to Salesforce? The problem is then I have to do this one-by-one each time which is hugely time consuming.

Does anyone know a better way to try to clean up my data for both Marketo & Salesforce?

[Itay_Billet4]

Regarding your first question, if you'll merge those in SF, it will be pushed back to Marketo (see article: https://community.marketo.com/MarketoArticle?id=kA050000000KyrM&src=comm)
There are some de-dupe solutions at the appexchange (http://appexchange.salesforce.com/results?keywords=dedupe), such as ringlead,DemandTools and cloudingo
You can also use Dupecatcher (which is free) to block new leads from being created manually.

[Anonymous]

As Itay noted, as soon as you create a duplicate Lead or Contact record in Salesforce, it will be synched to Marketo and create a duplicate lead record there.  If you subsequently merge the duplicate records in Salesforce, they will be merged in Marketo. 

If you are exporting the records from the acquired SFDC database, then importing them into your SFDC, it would be better to use one of the following tools to import them as they will prevent duplicate records from being created.

• The Apex Data Loader's Upsert function.  But first, you will need to set up a custom field in your SFDC's Lead, Contact and Account records as the unique record identifier from an external system that the Data Loader will use to match records. 
• The SFDC Lead Import Wizard and Account/Contact Import Wizard.  They will let you specify the matching criteria (e.g. Lead/Contact Name, Email Address, Company Name/Site) during the import process.

In both, if they detect a matching record, you can specify how you want your records to be updated with the data from the acquired SFDC database.